Table of Contents E6x Voltage Supply and Bus Systems Subject Page Voltage Supply and Bus Systems .5 Voltage Supply .5 System Components.7 Ground Points.7 Battery .8 Battery Service Information .8 Battery Cable .8 Intelligent Battery Sensor (IBS).9 Micro-Power Module (MPM).9 Rear Power Distributor with Terminal 30g Relay .9 Terminal 30g Relay (KL30g).9 Front Power Distribution.10 Ignition Starter Switch.10 CAS .10 Digital Engine Electronics (DME) .10 Starter Relay.10 Component Locations .11 Principle of Operation.14 System Functions .14 Electric Energy Management.14 Power Management .15 Battery Charge Balance .16 State of Health of the Battery.17 Variable Charging Voltage .17 BatteryTemperature .17 ConsumerCurrent.17 Idling Speed Increase .18 Load Peak Reduction .18 ConsumerShutoff.19 Convenience Consumers .19 Legally Prescribed Auxiliary Consumers .19 Auxiliary Consumers .19 System Related Run-on .19 Off-load Current Monitoring .19 Terminal 30g Relay .19 Initial Print Date: 12/04 Revision Date: Subject Page Intelligent Battery Sensor.20 Mechanical Section.20 IBS Measuring Ranges.21 Electronic Evaluation Module.22 IBS Hardware.23 IBS Software .23 IBS Functions.23 IBS Charge Management.24 Closed-Circuit M onitoring.24 IBS Wake-up .25 Servicing the IBS .26 IBS Diagnosis .26 Voltage M easurement.26 Current M easurement.27 Terminal 15 Wake-up Signal Faults .27 SoC/SoH .27 State of Charge.27 State of Health .27 Terminal 30g Relay.28 30g Switch On Conditions .30 30g Switch Off Conditions .30 Micro-Power Module.31 Normal Mode.31 M PM Switch-on Conditions .32 Switch-off Conditions.32 Sleep Mode .33 Service Information for M PM .34 Alternator.35 Digital Motor Electronics .35 Variable Battery Charging Voltage .36 Idle Speed Boost.36 Reducing Peak Loads.36 Electric Load Cutout.36 Battery Charge M anagement .37 Battery - State of Health .37 Data Transfer to the IBS .37 Closed-Circuit Current Diagnosis.37 Terminal 30g Relay.37 Subject Page Bus Systems .38 K-CAN .38 K-CAN Changes.38 MOST .39 Most Changes .39 byteflight .39 byteflight Changes.39 PT-CAN .39 Bus System Parameters.39 Sub-Bus Systems .40 LIN-Bus .40 LIN-Bus Main Controller.40 F-CAN .41 BSD (Bit-Serial Data Interface) .41 Sub-Bus System Parameters .42 MOST ConnectorJ unction.42 Bus System Overview (E61).43 Bus Systems (E63 and E64).44 Voltage Supply and Bus Systems Model: E60, E61, E63 and E64 Production: All ■Biiermis After completion of this module you will be able to • Understand IBS Operation • Explain Power management • Recognize bus systems on E60,E61, E63 and E64 • Diagnose voltage supply faults 4 E6xVoltage Supply and Bus Systems Voltage Supply and Bus Systems Voltage Supply The voltage supply on the BMW 5 and 6-Series is similarto that on the E65. However, the 5 and 6-Series do not have the power module from the E65. A network of hardware and software assumes the role of energy management. The energy management system monitors and controls the vehicle's energy requirements, both when driving as well as when stationary. The energy management system comprises the functions of the electric energy management system and the power management functions contained therein. The "State of Charge" (SoC) and the "State of Health" (SoH) of the battery are determined continuously with the power management system. vl) CAS Index Explanation Index Explanation 1 Intelligent Battery Sensor (IBS) 7 Starter relay 2 Battery 8 Rear power distribution box w/KL30g relay 3 Ignition/Starter switch 9 Front power distribution box 4 DME (ECM) 10 Car Access System (CAS) 5 Alternator 11 Micro-Power Module (MPM) 6 Battery 5 E6x Voltage Supply and Bus Systems The most important components and functions of the electric energy management system are: • The intelligent battery sensor (IBS) for continuous measurement of the battery values. • The software of the power management system in the Digital Motor Electronics (DM E) and in the IBS. • The terminal 30g relay, which is actuated by the Car Access System (CAS). • The micro-power module (M PM), which is located between the front and rear power distributors. New features of the power supply are: • IBS • Terminal 30g relay (terminal 30 active) . mpm • Ground point on "reduced-weight aluminum front end" (GRAV) Advantages of the power supply are: • Precise identification of the "State of Charge" (SoC) and "State of Health" (SoH) of the battery by the power management system. • IBS designed for use with different assembly groups. • Reduced off-load current: The consumers on terminal 30g are switched off in a defined manner by the terminal 30g relay. • A defined connection between the aluminum front end and the steel bodywork with the GRAV ground point in the engine compartment. • The GRAV ground point improves the vehicle's electromagnetic compatibility (EMC). • More headroom in the rear of the vehicle. The routing of the battery cables in the outer area allows the seats and carpets in the rear of the vehicle to be installed with reduced height. 6 E6xVoltage Supply and Bus Systems System Components The powersupply system consists of the following components: • Vehicle Ground Points • Battery • Battery Cable • Intelligent Battery Sensor with ground Lead (IBS) • Terminal 30g Relay • Micro-Power Module (MPM) • DM E • Car Access System (CAS) Ground Points The ground point (GRAV) improves the electromagnetic compatibility (EM C) of the vehicle. Aging connections between the front end and the remaining car body do not affect the EMC. The contact resis¬ tances between the front end and the remaining car body are bridged by means of the ground lead. Ground strap between aluminum and steel frame sections 7 E6x Voltage Supply and Bus Systems Battery The battery size depends on the engine and equipment configuration. Battery Service Information The battery size is coded in the DM E. Replacement batteries must be the same capacity rating as the original battery. Particular attention must be paid to the cables and the IBS when replacing a battery. Irreparable damage may occur if the cables and IBS are subjected to high mechanical stress and strain. Referto service information forthe IBS. As on the E65, the power management system is to be initialized by means of the diagnosis job "Control_battery_replacement_register." Follow the repair instructions. Battery Cable The battery cable is installed on the underside of the vehicle. The battery cable is moni¬ tored by the ASE system as in the E85. Sensor leads are routed from the battery cable to the left and right B Pillar satellites. Battery cable size is dependent on engine. M ost US vehicles use 120mm 2 aluminum Ribbon cable. C ross Section of battery cable with sensor lead u ndercar routing of battery cable 8 E6xVoltage Supply and Bus Systems Intelligent Battery Sensor (IBS) The IBS is a mechatronic, intelligent battery sensor with its own microcontroller. The IBS continuously takes measurements at the battery which include: • Terminal voltage • Charge current • Discharge current • Battery (electrolyte) temperature Micro-Power Module (MPM) When the vehicle is at rest, the MPM switches individual consumers off, if: • The off-load current is too high when the critical "State of Charge" (SoC) is reached • Undervoltage occurs • Too many "wake-up" circuits are activated in the K-CAN • The vehicle fails to go into sleep mode The micro-power module (MPM) is connected to the K-CAN and located in the luggage compartment. Rear Power Distributor with Terminal 30g Relay The rear power distributor is installed in the luggage compartment, (referto ETM forspecific location). The rear power distribution box is connected to the positive terminal of the battery, the front power distribution box and the external-start support point. The MPM is connected to the rear power distribution box (and the front power distribution). Terminal 30g Relay (KL30g) The terminal 30g relay is actuated by the Car Access System (CAS) and prevents increased off-load current by switching off individual consumers. KL30g Relay 9 E6x Voltage Supply and Bus Systems Front Power Distribution The front power distribution box (fusebox) is connected to the rear power distributor. The CAS and the starter motor are connected to the front power distributor. Ignition Starter Switch The ignition starter switch is located on the right- hand side of the steering column. The ignition starter switch is directly connected to the Car Access System (CAS). Front Power Distribution Box CAS The CAS comprises the functions: • Terminal control • Electronic immobilizer(EWS) • Evaluation of radio signals from remote control The CAS is directly connected to ignition starter switch by cables. The DME (ECM) and the starter motor are connected to the CAS. The CAS is part of the K-CAN bus network. Digital Engine Electronics (DME) The digital engine electronics system (DME) is responsible forengine management. The ECM includes the electronic immobilizer (EWS) and is also used for redundant (2-fold) data storage. The ECM is connected to the Powertrain CAN (PT-CAN) data bus to allow it to communicate with other control units in the vehicle. Starter Relay The starter relay switches the battery voltage to the starter motor, when: • The ignition starter switch is in switch position 2, • The CAS receives the correct information and transmits this to the DM E / DDE via the K-CAN, • The electronic immobilizer (EWS) actuates the starter relay. 10 E6xVoltage Supply and Bus Systems Component Locations E60 Rear Power Distribution Box 1. KL30g relay 2. Heated rear window relay Rear Power Distribution Box 11 E6x Voltage Supply and Bus Systems E63/E64 1. Rear window relay 2. Terminal 30g relay 3. Terminal 15 relay (soldered) 12 E6xVoltage Supply and Bus Systems E61 1. TV Antenna Amplifier, right (notfor US) 3. Rear power distribution box 2. Telephone emergency call antenna 4. Intelligent battery sensor (IBS) 1. Micro-power module (MPM) 2. Rear Hatch Lift M odule (HKL) 3. Trailer module (AHM) (notfor US) 4. Park distance control (PDC) 5. Electronic ride height control (EHC) 6. Load-shedding relay for E DC 7. Relay, rear window wiper 8. Relay, automatic soft close 9. Relay, compressorfor EHC 13 E6x Voltage Supply and Bus Systems Principle of Operation System Functions The power supply system comprises the following functions: • Electric energy management • Power management • Variable charge voltage • Idle-speed increase • Reduction of load peaks • Consumer shutdown • Off-load current monitoring • Terminal 30g relay Electric Energy Management The electric energy management monitors and controls the vehicle's energy require¬ ments. The monitoring and control functions are performed by the interconnection of var¬ ious components. The energy management links functions, signals and maps for gener¬ ating and outputting control signals. Components of the energy management system: • Battery • IBS • Bit-serial data interface (BSD) • DM E or DDE • Engine • Power management (microcontroller) • M icro-power module (M PM) • Alternator • Terminal 30g relay • Consumers on terminal 30/terminal 30g 14 E6xVoltage Supply and Bus Systems Function/systems involved in energy management: • Power management • Car Access System (CAS) Signals/maps in energy management system: • Current flow to consumers • Increased idling speed • Battery charge current • Nominal value for charge voltage • Consumer reduction • Terminal 15 wake-up wire Power Management The power management is on the one hand part of the electrical energy management system. Power management is software stored in the DM E and in the intelligent battery sensorthat is used for controlling the vehicle's energy requirements. Power management comprises the functions controlled by the software in the DM E and in the IBS: • Variable charge voltage forthe battery by adapting the charge voltage from the alter¬ nator to that required by the battery. • Increased idling speed to boost the alternator's output. • Reduction of load peaks through power reduction when the vehicle's electrical system is unable to provide the energy needed (vehicle electrical system deficiency). • Auxiliary consumers switched off via CAN messages when engine has reached its limit of starting capability. • Off-load current monitoring. 15 E6x Voltage Supply and Bus Systems Power management links the input signals with the characteristic curves stored in an EPROM (Erasable Programmable Read-Only Memory) and generates the output signals to control energy requirements. Power management components: • DM E or DDE • EPROM • Microcontroller (C) Power management input signals: • Battery voltage (U) • Current (I ±) • Temperature (T) Maps • Battery voltage (U) • Current (I ±) • Temperature (T) Output signals • Idle-speed control • Nominal value for charging voltage • Auxiliary consumer shutdown • Load peak reduction The power management system measures the "State of Charge" (SoC) and the "State of Health" (SoH) of the battery. Battery C harge Balance The charge balance of the battery is determined by the charge quantity flowing into and out of the battery. Two counters are provided in the power management to give a running balance of the battery's charge state. One ofthe counters counts the charge quantity taken up by the battery. Another counter counts the charge quantity discharged from the battery. Atthe factory, the counters are calibrated forthe battery fitted. The IBS transmits the data to power management in the DME / DDE. The data are transmitted via the bit- serial data interface (BSD). The difference between the two charge quantities is the battery's state of charge (SoC). Afterthe engine has been shut down, the power management will calculate the current SoC value when the engine is restarted. 16 E6xVoltage Supply and Bus Systems State of Health of the Battery The battery's state of health is derived from the drop in battery voltage during the starting procedure and from the starting current. These data are measured by the IBS during the starting procedure. The average value of the starting current in the start phase and the value of the voltage dip are transmitted to the DM E / DDE via the bit-serial data interface (BSD).The starting procedure is indicated to the IBS by currents greaterthan 200 amperes (A). The "engine running" signal is output by the DM E / DDE as soon as the engine starts. The power management system calculates the battery's internal resistance from the average value of the starting current and the value of the voltage dip. The internal resis¬ tance of the battery gives a good indication of the battery's State of Health (SoH). Variable C harging Voltage The variable charging voltage forthe battery ensures that an optimal battery charge state is maintained, even in unfavorable driving situations, unfavorable driving situations are, e.g. city traffic and driving in congested traffic. The charging voltage varies, depending on - Battery temperature and - Consumer current. B atte ry Te m pe ratu re The temperature-dependent adjustment of the battery charging voltage prevents an undesirable increase of the battery temperature during recharging. Moreover, the battery temperature remains lower, even at higher ambient temperatures. This reduces the amount of gas generated during charging and the amount of distilled water consumed. ConsumerCurrent The level of consumercurrent is measured by the IBS and transmitted to the power man¬ agement via the bit-serial data interface (BSD). From this, the power management derives the charging voltage level to be generated by the alternator. This charging voltage nomi¬ nal value, as derived by the power management, determines the level of the charging voltage generated by the alternator. This determines the battery charge current, which in turn influences the battery charging process, and ultimately the vehicle's consumer current. 17 E6x Voltage Supply and Bus Systems Idling Speed Increase The idling speed of the engine is raised by the DM E to 750 rpm if the specified battery charging voltage level is not achieved. The idling speed is raised when: • The alternator is at full capacity and • The battery's state of charge is too low. Load Peak Reduction If the charge state of the battery does not improve, even after the idling speed has been increased, the peak load in the vehicle electrical system is reduced. The peak load reduc¬ tion is achieved by the following actions: • Pulsing the load with pulse width modulation (PWM) signals In this process, consumers are switched on and off for defined times. • Power draw is reduced to a certain percentage. • Individual consumers are switched off in extreme situations when the power reduction achieved through pulsing and reduced consumption is insufficient. The load on the vehicle electrical system is reduced according to the table: Priority of consumers Power reduction Control unit Heated rear window Pulsing IHKA Seat heating Level 2 SM Seat heating 50% SM Active seat Off SM Heater blower 75% IHKA Steering wheel heating Pulsing SZL Heater blower 50% IHKA M irror heating Off TM Heated rear window Off IHKA Seat heating Off SM Steering wheel heating Off SZL Seat climate Off SM Heater blower 25% IHKA 18 E6xVoltage Supply and Bus Systems Consumer Shutoff Consumers are switched off according to different criteria and are split into the following categories: Convenience Consumers • Window heating • Seat heating • Steering wheel heating The convenience consumers are automatically switched off when the engine is switched off. The convenience consumers can only be switched on again after the engine has been restarted. Legally Prescribed Auxiliary Consumers • Side lights • Hazard warning lights Legally prescribed auxiliary consumers must still be operational when the engine has been switched off, as long as this is possible. These auxiliary consumers are not switched off, even if the battery's limit of starting capability has been reached. Auxiliary C onsumers • Independent heating • Independent ventilation • Communications components (Displays - Terminal 30g and Telematic services) The auxiliary consumers listed can still be switched on afterthe engine has been switched off. The auxiliary consumers are automatically switched off when the battery reaches its limit of starting capability. A CAN message from the DM E / DDE prompts the shutdown. System Related Run-on • Electric radiator fan System-related run-on components can remain operational for a certain time afterthe engine has been switched off. Off-load Current Monitoring If the battery current exceeds 80 milliamperes (mA) in off-load state (setting programmed at factory), a fault entry will be stored in the DM E / DDE. Terminal 30g Relay The terminal 30g relay prevents a higher off-load current, e.g. one caused by a defective consumer, with a predefined consumer shutoff. The terminal 30g relay is actuated by the CAS. The "g" indicates that terminal 30g is an active terminal. 19 E6x Voltage Supply and Bus Systems Intelligent Battery Sensor The IBS is a mechatronic intelligent battery sensor with its own microcontroller. It constantly measures the following: • Battery terminal voltage • Battery charge/discharge current • Battery acid temperature Installed directly at the negative battery terminal, care should be used when removing and installing the negative battery cable. The IBS consists of 3 functional elements: • Mechanical section • Hardware • Software Index Explanation Index Explanation 1 Pole Terminal 4 Screw 2 Shunt 5 IBS 3 Spacer Mechanical Section The mechanical part of the IBS consists of the battery terminal for the negative pole with ground cable. Tasks of the mechanical section of the IBS: • Providing electrical contact of the car body with the negative pole of the battery • To accommodate the sensor element for current measurement • To provide mounting forthe hardware • Providing sufficient thermal contact between the temperature sensor of the hardware and the negative pole of the battery • Providing protection forthe sensitive electronic components • The battery terminal provides the ground connection for IBS 20 E6xVoltage Supply and Bus Systems Index Explanation Index Explanation 1 Copper 4 Injection molding 2 Gullwings (tabs) 5 Copper 3 PC board with evaluation electronics 6 Manganin Manganin A copper alloy resistor of low resistance value, that maintains an extremely constant temperature, regardless of current flow. Used as a shunt resistorto measure current flow by the evaluation electronics ofthe IBS IBS Measuring Ranges • Voltage 6 V to 16.5 V • Current-200 A to+200 A • Closed circuit current 0 A to 10 A • Starting current 0 A to 1000 A • Temperature -40°C to 105°C 21 E6x Voltage Supply and Bus Systems Electronic Evaluation Module The electronic evaluation module of the IBS continuously registers the measured data. The IBS uses these data to calculate the following battery indicators. • Voltage • Current • Temperature The IBS sends the calculated battery indicators to the DM E via the BSD.The IBS calcu¬ lates changes in battery SoC/SoH based on information received from the DM E on the SoC of the battery during the period of time between engine "OFF" and deactivation of the DM E relay. Afterthe DM E relay has been switched off, the IBS continues to con¬ stantly observe the SoC of the battery. r 02915.02 22 E6xVoltage Supply and Bus Systems IBS Hardware IBS Hardware consists of the following: • Shunt for current measurement • Temperature Sensor • M ulti-layer pc-board as the electronic circuit including the electronic components. 02916_02 IBS Software The software in the PC-board of the IBS calculates State of Charge and State of Health of the battery and sends the information to the DM E. Communication with the DM E, which takes place via the BSD, allows the DM E to obtain data constantly from the IBS during vehicle operation. IBS Functions The following functions are integrated in the IBS: • Continuous measurement of current, voltage and temperature of the battery under all vehicle operating conditions • Calculation of battery indicators as basis for SoC and SoH • M onitoring of battery charge/discharge current • Monitoring of SoC and notification to DM E of critical SoC • Partial calculation of SoH Based on starter draw • Closed-circuit current monitoring in vehicle • Data transfer to DM E • Self-diagnosis • Self wake-up capability during sleep mode 23 E6x Voltage Supply and Bus Systems Index Explanation Index Explanation 1 Battery positive 5 C urrent measurement 2 Battery negative 6 M icrocontroller (in IBS housing) 3 Battery voltage measurement 7 BSD (Bit Serial Data line) 4 Temperature measurement 8 DME (ECM) IBS Charge Management The IBS continuously manages the charge status of the battery when the key is off. The current SoC is stored in the IBS every 2 hours. When the IBS receives the terminal 15 "wake up signal" the DM E is updated with the current values of the battery indicators. C losed-C ircuit Monitoring When the vehicle is off the IBS is programmed to wake up every 40 seconds so that it can update the measured values (Voltage, current, temperature).The measuring time of the IBS is approximately 50 ms. The DM E reads the history of the measurements on start-up. An entry is made in the fault code memory of the DM E if a closed-circuit current draw was present. 24 E6xVoltage Supply and Bus Systems VS223_02372JI2 IBS Wake-up When the key is switched off, before the DM E enters sleep mode, the DM E informs the IBS of the current SoC of the battery. The IBS monitors the SoC and when it drops below the programmed threshold, a wake-up signal is sent to the DME via the BSD. The DME wakes up, obtains information on the current SoC of the battery from the IBS and requests the auxiliary electrical loads to switch off. After one wake-up sequence the IBS is prohibited from waking the vehicle again during this key off cycle. The vehicle subsequently reassumes sleep mode. 25 E6x Voltage Supply and Bus Systems Servicing the IBS The IBS is very sensitive to mechanical stress and strain. It is serviced as a complete unit with the ground cable.The ground cable also serves as a heat dissipaterforthe IBS. Particular attention should be paid to the following points in service: • Do not make any additional connections at the negative terminal of the battery • Do not modify the ground cable • Do not make any connections between the IBS and the sensor screw • Do not use force when disconnecting the ground terminal from the battery • Do not pull at the ground cable • Do not use the IBS as a pivot pointto lever off the ground terminal • Do not use the connections of the IBS as a lever • Use only a torque wrench as described in the repair manual • Do not release ortighten the sensor screw A fault code is stored in the DM E when the IBS is defective. The DM E adopts a substi¬ tute value and assumes IBS emergency mode. IBS emergency mode boosts the idle speed in order to sufficiently charge the battery. Note: The software in the DME and that of the IBS must match. To ensure this requirement it may be necessary to replace the IB S in connection with a software update. IBS Diagnosis The IBS features a fault code memory that is read out by the DME. Self diagnosis checks the voltage, current, temperature measurement, terminal 15 wake up as well as system errors in the IBS. Direct diagnosis of the IBS is not possible, it must be diagnosed through the DME. Voltage Measurement If the IBS is shorted to ground, a DM E fault code will display "Voltage Fault DM E ON". The IBS will be unable to wake up the DME. If the IBS is shorted to B+, a DM E fault code will display "Voltage fault, DM E not ON" and no charging current. The vehicle will NOT enter sleep mode. 26 E6xVoltage Supply and Bus Systems Current Measurement Current measurement is a very dynamic process, indicated by the measuring range of mA to kA. The fault code "Current Fault" is entered in fault memory when an implausible value is determined during the plausibility check of the various measuring ranges of the IBS. Terminal 15 Wake-up Signal Faults The IBS recognizes wake-up line faults. The IBS can detect a wake-up line error underthe following conditions: • DME "ON" • Terminal 15 "ON" (voltage high at IBS) • Terminal 15 running via BSD IfTerminal 15 at the IBS and Terminal 15 via the BSD are not equal, a fault is indicated in the BSD line or an IBS Fault. The IBS fault may be caused by: • Terminal 15 Driver in the IBS has a short to ground • Terminal 15 Driver in the IBS has a short to B + oris defective. SoC/SoH State of Charge SoC is a calculated condition showing the current charge in the battery. The SoC calcula¬ tions are performed by the DME. SoC is used during key off periods to insure the bat¬ tery maintains a sufficient charge to start the engine at least one more time. State of Health SoH tracks the history of the battery in the vehicle. Charge/discharge cycles and times are monitored. SoH helps the DME determine the proper charging rates and anticipated bat¬ tery life. The IBS detects vehicle start based on current draw in excess of200A. The engine run¬ ning signal is made available by the DME via the BSD. Internal resistance of the battery is calculated from the current and voltage dip. These indicators are forwarded to the DME. From this data, the DM E the state of health (SoH) of the battery. 27 E6x Voltage Supply and Bus Systems Terminal 30g Relay The Terminal 30g Relay prevents increased closed-circuit current consumption by switching off electric loads. The switch-off procedure disconnects various electric loads in a defined mannerfrom the vehicle electrical system.This happens approximately. 60 minutes afterterminal R "OFF." The deactivated electric loads are activated again together with terminal 30g "ON." The terminal 30g relay is actuated by the car access system. Powerto the following control units is managed by the terminal 30g relay: • Center console switch center (SZM) • Rain and low beam sensor(RLS) • Controller • Central information display (CID) • S lide/tilt sunroof (S FI D/M DS) • Satellite radio (SDARS) • TOP HiFi amplifier • Telephone • Flead-up display (FIUD) • Active cruise control (ACC) • Electronic transmission control/SMG • Dynamic stability control (DSC) • Adaptive cornering light (AH L) Terminal 30g relay location 15 5 0 15 R 5 15 ' TWi 60 r min ' I i i 1 I 'I'l j * aus " - r i KcT —1 aus i _i_ | 1 1 _| | l 1 1 1 i i i i i i t t i 28 E6xVoltage Supply and Bus Systems 30g and MPM System Schematic Index Explanation Index Explanation 1 Battery 7 DM E (ECM) 2 BST 8 DME (ECM) Relay 3 Rear power distribution w/KL30g and KL15 relays 9 CAS 4 Front power distribution box 10 MPM 5 Starter motor 11 IBS 6 Alternator 29 E6x Voltage Supply and Bus Systems 30g Switch On Conditions The switch-on conditions forterminal 30g relay are as follows: • Unlock vehicle or • Terminal R or • Status change of door contacts or of trunk contact or • Telephone wake-up line fortelematic services or • Service applications 30g Switch Off Conditions The switch-off conditions forterminal 30g relay are as follows: • 60 minutes after terminal R "OFF" or • Service applications • Power M anagement Switch off Kl. 30L Index Explanation Index Explanation 1 Input signal/Terminal 30g OFF/ON 4 Electric Load 2 Car Access System (CAS) KL30 L Terminal 30 (load) 3 Terminal 30g Relay 30 E6xVoltage Supply and Bus Systems Micro-Power Module In the same way as with terminal 30g, the micro¬ power module (MPM)facilitates defined deactivation of electric loads. The M PM is installed in the spare wheel recess and operates in 3 modes, normal mode, sleep mode and service mode. Normal Mode All functions of the M PM are available in normal mode. The M PM switches on/off the voltage supply to the electric loads involved in communication. Loads are switched on and off only when a fault occurs during the vehicle rest period. The M PM switches the voltage supply on and off in the following control units: • M ulti-audio system controller M-ASK • Car communication computerCCC • CD disc changerCDC • DVD changer DVD The supply voltage is switched on and off by means of a bistable (switchovertype) relay. The relay is set to "ON" when it leaves the factory. This type of relay has two positions, On and OFF. When ON voltage is passed from Fuse 57 through the M PM to the above consumers. When OFF, the connection to F57 is broken.This type of relay does not need power (coil energized) to maintain either switch position. Power is only needed to MPM 12V 6136-6939666-01 HELBAKO 66892110 041280766 6291 ■ HW 00.3 FSVS.10 24 194 / 31 E6x Voltage Supply and Bus Systems MPM Switch-on Conditions The conditions required for switch-on are: • Initial application of battery voltage ("first switch to power") to the MPM in the factory. This action makes sure that the MPM has switched through, even without further conditions required for switch-on. • Lock/unlock • Terminal R ON • Terminal 15 ON • Changes in condition of door contacts or boot-lid-contact switch. Switch-off Conditions The conditions required for switch-off are: • Off-load current at critical State of Charge (SoC - battery's limit of starting capability). • "Auxiliary consumers OFF" signal from DME / DDE for off-load current of more than 80 milliamperes (mA). • SoC below battery's limit of starting ability. All auxiliary consumers must be signed off immediately if: • Undervoltage Battery voltage less than 9 volts (V)fora period of time greaterthan 60 seconds (s). • Permissible number of "wake-up" actions in K-CAN exceeded. • Bus activity after 60 minutes, even though vehicle has been parked up (terminal 0). • The time is reset by switch-on conditions, e.g. by a door being opened. This means:The vehicle is unable to go into sleep mode afterterminal R is switched OFF. There is no limit to the number of times this process can be repeated. It could thus cause the battery to become discharged! When it is switched off, the bistable relay separates the consumers from the vehicle elec¬ trical system with a time lag of 5 minutes. The switching-off process is interrupted if any of the switch-on conditions occurs during these 5 minutes. The switch-on condition has priority over the switch-off condition. 32 E6xVoltage Supply and Bus Systems Index Explanation Index Explanation 1 Rear power distribution w/KL30g and KL15 relays 7 DME (ECM) 2 MPM K-CAN Body Controller Area Network 3 Front power distribution box KL15 Terminal 15 4 Electrical Load KL15 WUP Terminal 15 Wake up 5 Electrical Load BSD Bit-serial Data Line 6 Battery The M PM communicates with the vehicle through the K-CAN and is supplied power by both a KL 30 and a KL 15. If terminal 30 voltage is lost, operation continues with the volt¬ age supplied by terminal 15, and a fault is registered. Sleep Mode The MPM assumes sleep mode approximately! s afterthe K-CAN has gone into sleep mode. The current switching status of the relay is stored before the MPM assumes sleep mode. The MPM is woken by the terminal 15 signal via the K-CAN or by activation of KL15. On waking, the switching status of the relay last stored is reestablished. 33 E6x Voltage Supply and Bus Systems • Locking/unlocking vehicle • Terminal R - ON • Terminal 15 - ON • Status change of door ortrunk contacts • K-CAN Activity Last status stored in EEPROM J 02968.02 • Closed circuitcurrenttoo high atcritical SoC with "auxiliary load OFF" signal • Undervoltage <9Vfor >60s • Numberof K-CAN wake up procedures exceeded • Bus activity after 60 minutes despite vehicle being shutdown Service Information for MPM A fault code is stored in the fault code memory when the M PM disconnects the electric loads from the vehicle electrical system. The following fault codes can be read out in diagnosis: • Terminal 15 fault • Deactivation with information on the switch-off condition The information on the switch-off condition is stored in the info memory: • Undervoltage • Contact fault of relay contacts 34 E6xVoltage Supply and Bus Systems Alternator Bosch and Valeo alternators are installed in the 5 and 6 series. The alternators are fitted depending on the type of engine and equipment configuration. They differ with regard to their rating of 140 A and 170 A and are air-cooled. Digital Motor Electronics The power management software is contained in the DME. When the vehicle is at rest, the IBS is partially responsible for power management. The tasks of the power management system include: • Adaptation of the alternator charging voltage. • Idle speed boost for increasing the power output of the alternator. • Reduction of peak loads in the event of a shortfall in coverage provided by the vehicle electrical system. • Deactivation by means of bus messages of electric loads such telephone, on reaching the start capability limit of the vehicle. • Closed-circuit current diagnosis. INPUT OUTPUT — e; 10 VS223_02373_02b Index Explanation Index Explanation 1 Battery Voltage 6 EEPROM with maps for voltage, current & temp 2 Current input 7 Idle speed control 3 Temperature input 8 Specified alternator charging voltage 4 DME (ECM) 9 Deactivation of electrical loads 5 Power management 10 Peak load reduction 35 E6x Voltage Supply and Bus Systems Variable Battery Charging Voltage The variable battery charging voltage on system ensures improved charging manage¬ ment of the battery in unfavorable driving situations. The power management controls the temperature-dependent voltage for the charging voltage of the alternator via the BSD line. Idle Speed Boost The idle speed can be increased in situations where the battery does not cover power requirements. When the specified voltage alone is no longer sufficient, the DM E boosts the idle speed corresponding to the engine status. Reducing Peak Loads The peak load of the vehicle electrical system is reduced when there is still a shortfall in battery coverage despite boosting idle speed. Peak load reduction is realized by: • Reducing power output, e.g. by correspondingly controlling the clock cycles of the rear window defogger. • If reducing the power output is not sufficient, individual electric loads can be switched off in extreme situations. Electric Load Cutout The electric loads in the E60, E63 and E64 are divided into the following categories: • Comfort loads, e.g. window defogger, seat heating, steering wheel heating. Electric loads switch off automatically after engine "OFF." These electric loads can be acti¬ vated again after the vehicle has been restarted. • Legally required auxiliary electric loads, e.g. side lights, hazard warning lights. Legally required auxiliary loads must be operational fora certain period of time after engine "OFF." These legally required electric loads are not switched off even on reaching the start capability limit of the battery. • Auxiliary electric loads, e.g. independent ventilation,communication components such as central information display, telephone, telematic services. Auxiliary loads can be switched on after engine "OFF." The comfort electric loads switch off auto¬ matically on reaching the start capability limit of the battery. Switch-off is requested by the DM E in the form of a CAN message. • System-related after-running loads, e.g. electric radiatorfan. System-related after¬ running loads can maintain operation fora defined period of time. 36 E6xVoltage Supply and Bus Systems Battery C harge Management There are two "counters" in the power management module. One counter is responsible for the battery charge and the other is for the battery discharge level. The state of charge (SoC)ofthe battery is formed by the difference between the charge acceptance and draw level. The power management receives the corresponding data from the IBS via the BSD. The power management calculates the current SoC value on restarting the vehicle. Battery - State of Health The IBS measures the dip in the battery terminal voltage and the starting current of the starter when the vehicle is started. The IBS detects vehicle start based on current draw in excess of 200 A. The engine running signal is made available by the DME (ECM). Internal resistance of the battery is calculated from the current and voltage dip. Starting current and voltage dip values determined during the startup process are trans¬ ferred via the BSD to the DM E (ECM). From this data, the power management calculates the state of health (SoH) of the battery. Data Transfer to the IBS The following data are transferred via the BSD to the IBS before the DM E assumes sleep mode: • State of charge of the battery SoC • State of health of the battery SoH • Outside temperature • Available discharge level • Terminal 15 wake-up enable • Terminal 15 wake-up disable • DM E close C losed-C ircuit C urrent Diagnosis A fault code is stored in the DM E when the battery current exceeds a defined value dur¬ ing the vehicle rest phase. The vehicle should be analyzed accordingly. Terminal 30g Relay The terminal 30g relay is actuated by the CAS at an excessively high closed-circuit cur¬ rent or on reaching the start capability limit of the battery. 37 E6x Voltage Supply and Bus Systems Bus Systems LS-DU5 Bus Network (E60) byteflight PT-CAN K-CAN K-CAN Changes In the E60, the bus systems K-CAN S and K-CAN P of the E65 were combined to form the K-CAN. The car access system CAS is no longer used as a repeater between K-CAN S and K- CAN P. CAS is now only a K-CAN user. The internal designation is CAS 2. The instrument cluster and the central information display are now connected to K-CAN. They no longer serve as a gateway between K-CAN S and MOST. The door modules are no longer connected to K-CAN P butratherto byteflight. The controllerCON is connected directly to K-CAN and no longervia the centre console switch centre SZM. 38 E6xVoltage Supply and Bus Systems MOST MostChanges MOST has less users than on the E65. Components such as the instrument cluster and central information display CID are connected to other bus systems. The MOST additionally features the satellite radio (SDARS). A large M OST system extending up to the luggage compartment is installed if the E60 is equipped with a telephone, orTop HiFi system. by tef light byteflig ht C hanges The SIM and ZGM functions have been combined in the SGM .The door modules adopt the functions of the front door satellites. byteflightE65 byteflig ht E 60/ E 63/E 64 Central Gateway Module Safety and Gateway Module (SGM) Safety and Information Module Combined in SGM Steering Column Switch Center (SZL) SZL Center Vehicle Satellite (SFZ) SFZ (E64 uses SFZ-R) A-pillar satellite, lefts AS L not used A-pillar satellite, right SASR not used F rant door satellite, left ST VL Driver's door module TM FA F rant door satellite, right STVR Passenger door module TMBF B-pillar satellite, leftSBSL SBSL B-pillarsatellite, right SBSR SBSR Driver's seat satellite SSFA not used Passenger seat satellite SSBF not used Rear seat satellite SS H not used PT-CAN No Changes Bus System Parameters Bus System Data Rate Bus Structure K-CAN 100 kbps Linear/two wire - copper PT-CAN 500 kbps Linear/two-wire - copper byteflight 10 Mbps Star/Fiberoptic MOST 22.5 Mbps Ring/Fiberoptic D-Bus 10.5/115 Kbps Linear/S ingle-wire 39 E6x Voltage Supply and Bus Systems Sub-Bus Systems LIN-Bus The LIN-bus was developed to provide a standard network forthe automobile industry. The LIN-bus is a standardized serial single-wire bus system. The LIN bus facilitates fast and simple data transmission. The use of LIN-bus technology reduces the number of lines in the vehicle. LIN-bus systems in E60 A typical LIN-bus system includes the following components: • 1 Main Controller • Several Server Units • Single-wire line On the E60, the LIN bus is used on the IHKA system, the SBFA and the AHL system. Main Controller Server Unit(s) IHKA Flap (stepper) motors and Blower motor DoorModule Driver’s Switch Block (SBFA) AHL (Adaptive Head Lights) Stepper Motor Controller (SMC) The LIN-bus uses a bi-directional single-wire bus line as the transmission medium. The bus contains only one Main Controller while many server units are possible. The transfer rate on the LIN-bus can be up to 19.2 kBaud. The following transfer rates are possible: 9.6 kBaud for IHKA 19.2 kBaud for other systems LIN-Bus Main Controller The LIN-bus Main Controller transfers the control unit requests to the server units of the system. The LIN-bus Main Controller controls the message traffic on the bus line. LIN-bus server units of the air conditioning systems include: • Actuator motors forthe air distribution flaps • Blower controller The LIN-bus serverunits waitforcommands from the LIN-bus Main Controllerand communicate with it only on request. 40 E6xVoltage Supply and Bus Systems F-CAN The F-CAN enables fast data transfer between the chassis related system components (e.g.active steering, DSC etc.) \i) >. ttf. - r §1% 3 k N' - 'll'"") F-CAN BSD (Bit-Serial Data Interface) 1. DSC Sensor 1 2. DSC Sensor2 3. Active Steering Actuator (Summation steering angle sensor) 4. SZL 5. DSC 6. AFS VS223_02302.02 1. Alternator (GEN) 2. BSD 3. DME (ECM) 4. IBS 02073J32 41 E6x Voltage Supply and Bus Systems Sub-Bus System Parameters Sub-bus system Data rate Bus Structure Components BSD 9.6 Kbps Linear/Single wire DM E, IBS, Alternator DWA K-Bus 9.6 Kbps Linear/Single wire UIS, DWA Siren w/tilt sensor K-Bus seat 9.6 Kbps Linear/Single wire Seat adjustment switch unit, Centerconsole switch unit LIN Bus A/C (IHKA) 9.6 Kbps Linear/Single wire IHKA, All IHKA stepper motors, blower motor LIN Bus RDC (notforUS) 9.6 Kbps Linear/Single wire RDC, wheel arch antennae LIN Bus AHL 19.2 Kbps Linear/Single wire AHL Control unit, SMC LIN BusTMFA 19.2 Kbps Linear/Single wire Door module, Driver's switch block F-CAN 100 Kbps Linear/Two wire AFS, ARS, yaw rate sensors, SZL, DSC, LWS MOSTConnectorJ unction The M OST connector junction facilitates quick connection of new control units. 42 E6xVoltage Supply and Bus Systems Bus System Overview (E61) The bus system on the E61 contains additions to K-CAN. EHC and HKL are added with the MDS control unitforthe panoramic sunroof. The MOST bus, byteflight and PT-CAN have remained mostly unchanged. The sub-bus systems are as used on E60. K-CAN MOST OyfeMgM PT-CAN 0451 / 04 43 E6x Voltage Supply and Bus Systems Bus Systems (E63 and E64) The bus system on the E63/E64 is mostly the same as the E60. Due to the sunroof design in the E63, there is no SHD module but rather an Multi-Drive Sunroof module (M DS). Also, there is no passenger seat module on the E63/E64, so the K-CAN only has the SM FA. D-Bus K-CAN MOST byteflight PT-CAN 03694 _ 03 c 44 E6xVoltage Supply and Bus Systems Workshop Exercise - Battery and Power Supply Using an instructor designated vehicle, connect appropriate diagnostic equipment and perform complete vehicle short test. Describe how to access the test module for "battery replacement register": What is the importance of performing this test module after replacing a battery? List the last battery replacement mileage for: Last Second Third _ Fourth Go to the "closed circuit current" test module in the service functions menu and record the time/current values below: 0 - 80ma _ _ 80 - 200ma _ _ 200 - lOOOma _ >1000ma _ How is this information useful in diagnosis? Can you resetthe "histogram" in this test module? 45 E6x Voltage Supply and Bus Systems Workshop Exercise - Intelligent Battery Sensor Using an instructor designated vehicle, connect appropriate diagnostic equipment and perform complete vehicle short test. Locate and Identify the IBS in the vehicle. Connect oscilloscope to BSD What is observed regarding the BSD signal? (Voltage etc.) Disconnect BSD connector and measured signal on both ends of the open connection. Compare both signals. What is observed regarding the signal from the DM E and the IBS? Reconnect BSD connector and monitor signal of BSD when entering sleep mode. What happens to the BSD when entering sleep mode and How long does the BSD stay active? Perform the test plan B1362 as outlined in the DISplus. Why is it important that replacement batteries be the same type and capacity as the factory installed battery? What measurements are performed directly by the IBS? 46 E6xVoltage Supply and Bus Systems Workshop Exercise - Terminal 30g Relay Using an instructor designated vehicle, connect appropriate diagnostic equipment and perform complete vehicle short test. Remove Terminal 30g relay and perform complete vehicle short test What control modules where not identified during the short test? What control module is responsible for switching the control circuit of the KL30g relay? With the KL30g relay still removed attempt to start the vehicle. Does the vehicle start? Why or Why not? What circuits are affected? How long afterterminal R "OFF" is the terminal 30g relay switched off? What conditions will cause the KL30g relay to be switched on when in sleep mode? 47 E6x Voltage Supply and Bus Systems Workshop Exercise - Micro Power Module Using an instructor designated vehicle, connect appropriate diagnostic equipment and perform complete vehicle short test. Access correct ETM for MPM circuit. What fuse supplies the load circuit powerforthe M PM? What circuits are supplied by the MPM? Unplug the MPM and observe which circuits are inactive. Which circuits are inactive with MPM disconnected? Using the oscilloscope obtain the scope pattern (dual trace) for pins 3 and 11 (K-CAN) of the MPM. What is observed regarding this scope pattern? (voltage etc) What are the pin numbers of the M-ASK that provide K-Can communication? If the M-ASK is not recognized during the short test would the OPPS testerbe useful? 48 E6xVoltage Supply and Bus Systems Classroom Exercise - Review Questions What are the power management tasks performed by the DME? Under what conditions (concerning the electrical system) does the DM E boost the idle? How does the DM E determine SoC? What is the difference is between SoC/SoH? How does the IBS detect starter operation? Explain IBS wake-up disable. Which control module is the gateway from the K-Can to the MOST? 49 E6x Voltage Supply and Bus Systems ^ C lassroom Exercise - Review Questions 8. Name the Bus orsub-bus systems that consist of two wires. 9. What is the purpose of the M OST connectorjunction? 10. What are some of the symptoms of a failed MOST Bus? 11. Which control unit calculates the SoC/SoH of the battery while the engine is running? 12. How often is the battery conditioned monitored while the vehicle is "OFF"? 13. How does the IBS signal the DM E of significant changes in SoC during "OFF" time? 50 E6xVoltage Supply and Bus Systems Workshop Exercise - Diagnosis Vehicle/M odel Chassis #: Complaint: Cause: Correction: 51 E6x Voltage Supply and Bus Systems