Table of Contents E70 Energy Management Subject Page The Energy Circuit in the Vehicle.5 Power Management .6 Idle Speed Boost .6 Charging Voltage Target Value .6 Emergency Operation.7 APM Control System .7 Electric Load Reduction .7 Fuel Consumption Reduction Measures .8 Advanced Power Management.9 Energy Flow.9 Information Flow.10 Diagnosis Information .11 Vehicle in Stationary M ode (terminal R and terminal 30) .12 Electric Loads in Stationary M ode.12 Stationary Load Log-off.12 Terminal 30g and Terminal 30g_f.12 Terminal 30g and Terminal 30g_f relay .14 Time-dependent Deactivation .14 Fault-dependent Deactivation.14 Terminal 30g_f Relay Switch-on and off Conditions .14 Continuous Positive .15 General M easures .16 Components.17 Intelligent Battery Sensor (IBS) .17 J unction Box.19 Engine Management (Power Management).20 Transport Mode .21 Closed-circuit Current.23 Electrical System and Battery Diagnosis .24 Energy Management - Diagnosis in Vehicle.25 E nergy H istory M emory.27 Memory Cycle .27 Driving Profile and Stopped Profile .27 Sleep Blockers .28 Bus Wake-ups .28 Intact Vehicle .29 Initial Print Date: 10/06 Revision Date: Subject Page Defective Vehicle .30 Data Record.33 Sleep Blockers.33 Number of bus wake-ups, driving profile/stopped profile .33 Bus Wake-up IDs .34 Data Record Storage.34 Ring M emory.35 Subject Page Energy Management Model: E70 Production: From Start of Production ■BIICTItfIS After completion of this module you will be able to: • Locate and Identify Energy M anagement System Components • Understand E70 Energy Management 4 E70 Energy Management The E nergy C ircuit in the Vehicle As in the current models, an energy management system is used in the E70 to ensure balanced energy management in the vehicle. The energy management functions are integrated in the power management system that is implemented in the form of software in the engine control unit. Index Explanation 1 Engine 2 Alternator 3 Intelligent Battery Sensor 4 Battery 5 J unction Box 6 Electrical load (i.e. headlights) 7 Engine management with integrated power management 5 E70 Energy Management Power Management The power management establishes the control processes in the area of energy management of our vehicles. A basic distinction is made between two types of power management: • Basic Power Management (BPM) • Advanced Power Management (APM) Only the advanced power management APM is used in the E70. In addition to the main functions of the basic power management, idle speed and of charging voltage target value, this system includes the following expanded functions: • Electric load reduction • Electric load shut-down • Vehicle systems diagnosis • Battery diagnosis Idle Speed Boost Despite the alternator operating at maximum, on gasoline engine vehicles the idle speed is increased by up to 200 rpm as soon as current is drawn from the battery. Charging Voltage Target Value The charging voltage at the alternator is controlled dependent on the temperature. The temperature value is made available by the Intelligent Battery Sensor (IBS). The power management uses this value as the input variable for calculating the battery tem¬ perature. With the aid of a calculation model, the specified charging voltage is set based on the battery temperature. This information is sent to the alternator via the Bit-serial Data Interface (BSD). Index Explanation 1 Model- based battery temperature of 8 degrees Celsius 2 Model- based battery temperature of 15 degrees Celsius 6 E70 Energy Management Emergency Operation The APM makes use of emergency operation functions when there is a break in the BSD interface. In this case, the alternator voltage is set to a constant 14.3 V. A fault code "Communication BSD" is entered in the fault code memory of the engine management. APM Control System Index Explanation 1 Advanced Power M anagement 2 Idle Speed Boost 3 Engine 4 Charging voltage target value 5 Alternator 6 Electrical load reduction 7 Electrical loads 8 Electrical system and battery diagnosis 9 BMW diagnostic system 10 Intelligent battery sensor 11 Battery data Electric Load Reduction When the vehicle is equipped with APM (advanced power management), in addition to increasing the idle speed and the specified charging voltage, the output of various electric loads can be reduced orthe loads can be switched off in orderto reduce the power consumption in critical situations. The electric loads are shut down only underthe following two conditions: • Battery charge status in critical range • Alternator fully utilized 7 E70 Energy Management Fuel Consumption Reduction Measures The following measures are activated underthese preconditions: Sequence Function Operation Control Unit i — 1 Rear Window Clocking IHKA 2 Seat Heating, rear compartment Stage 2 FKA 3 Electrical auxiliary heater, rear compartment 75 % FKA 4 Seat heating, front Stage 2 SMBFA SMBF J B 5 Seat heating, rear compartment Stage 1 FKA 6 Electrical auxiliary heater, rear compartment 50 % FLA 7 Seat heating, front 50 % SMBFA SMBF J B 8 Electrical auxiliary fan, 3rd row seating 50 % IHKA 9 Heater blower 75 % IHKA/FKA 10 Electrical auxiliary heater, rear compartment 25 % FKA 11 Steering wheel heating OFF FRM/| B 12 Electrical auxiliary heater, rear compartment OFF FKA 13 M irror heating OFF FRM/I B 14 Active seat OFF SM FA SMBF 15 Steering wheel heating OFF IHKA 16 Electrical auxiliary fan, 3rd row seating OFF IHKA 17 Seat heating, front OFF 18 Seat heating, rear compartment OFF FKA 19 Rear window OFF IHKA 20 Heater blower 50 % IHKA/FKA 21 Heated windshield OFF SM FA SMBF 22 Heater blower 25 % IHKA/FKA Note: All measures are implemented in the specified order. 8 E70 Energy Management Advanced Power Management Energy Flow During vehicle operation, the mechanical energy of the engine is converted by the alternator into electrical energy and made available to the electric loads. The electric loads receive their power supply mainly via terminal 30g and via terminal 30g_f. Certain electric loads are also still supplied directly by terminal 30 or by terminal R. For example, the anti-theft alarm system (DWA) must still remain active when the vehicle is parked. Index Explanation Index Explanation 1 Electric loads 5 Vehicle battery 2 Drive motor 6 Control units 3 Alternator KL30g Terminal 30, switched 4 Intelligent Battery Sensor KL30g_f Terminal 30 switched, fault dependent 9 E70 Energy Management Information Flow The calculations necessary for controlling the energy balance take place in the power management. The idle speed and charging voltage are regulated while the engine is running. The power intake of electric loads with relatively high power consumption is reduced orthe loads are switched off as required. Certain electric loads can be switched off when the engine is stationary. This takes place eithertime-controlled via the CAS and the terminal 30g relay or in response to electrical faults via the engine control, junction box and the terminal 30g_f relay. © 6 J 2 5 a Index Explanation Index Explanation 1 Electrical loads 4 Intelligent battery sensor 2 Engine 5 Vehicle battery 3 Alternator 6 Control units 10 E70 Energy Management Diagnosis Information The control units forthe engine management, junction box and footwell module provide various information forthe purpose of realizing effective diagnosis. Information relating to the status of the vehicle battery is stored in the engine management (engine control). Information on the functional sequences in the various bus systems is stored in the junction box. The BMW diagnosis system can access and evaluate this information. The BMW diagnosis system features an evaluation software that facilitates assessment of the history values and indicates the cause of problems as the result. This result must be assessed by a technician in orderto find the correct cause of the fault. Index Explanation Index Explanation 1 BMW Diagnostic system 4 Bus systems 2 Engine management 5 J unction box control unit/Footwell module 3 Vehicle battery with IBS 11 E70 Energy Management Vehicle in Stationary Mode (terminal R and terminal 30) Electric Loads in Stationary Mode Certain electric loads may be active even when the closed-circuit current monitoring facility of the power management is already in operation. This is necessary for various reasons: • Legally required electric loads, e.g. side lights, hazard warning system • Convenience forthe customer, e.g. radio function, telephone These electric loads must be excluded from the closed-circuit monitoring system in order to avoid misinterpretation in the power management. Forthis purpose, these electric loads must log in with the power management. In turn, the power management recognizes the activity and accepts the higher power consumption when the systems are deactivated, the corresponding control units log off from the power management. Stationary Load Log-off The power management in the engine control can send a request to switch off the active electric loads in stationary mode depending on the battery charge status and the start capability limit. As a result, the stationary loads must deactivate theirfunctions irrespective of the terminal status and must reach their closed-circuit current within 5 minutes. Legally required electric loads are excluded from this function. Terminal 30g and Terminal 30g_f The E70 is equipped with various relays for switching off the power supply to most control units. There are two terminal 30g relays in the front and rear power distribution boxes. The terminal 30g_f relay in the rear power distribution box is required forthe following optional equipment: • Multi-audio system controller • Car communication computer • Comfort Access • Instrument cluster • Telephone US/telephone preparation US 12 E70 Energy Management The relays are controlled by following control units: • Terminal 30g_f- activation by the junction box control unit The calculation necessary for activating the terminal 30g_f relay takes place in two control units. The following activities are monitored in the junction box control unit: - Invalid wake-up procedures within the bus systems - Sleep blockers (control units that constantly keep the bus systems active) The battery values are constantly read and evaluated in the engine control unit. The relay is also switched off when the starting capability limit of the vehicle battery is reached. • Terminal 30g - activation by the CAS Description Explanation KL15 Ignition (position 2) KL R Accessory (position 1) KL 30 B +Constant KL 30g B+, time dependent KL 30 g_f B+, fault dependent 13 E70 Energy Management Terminal 30g and Terminal 30g_f relay Time-dependent Deactivation The terminal 30g relay switches off the connected electric loads after 30 minutes. The after-running time is extended to 60 minutes if a telephone or auxiliary heating system is installed in the vehicle. The terminal 30g relay is activated by the CAS. Fault-dependent Deactivation The terminal 30g_f relay is activated by the junction box control unit and switches off the connected electric loads if a fault occurs. The terminal 30g_f relay is a bistable relay. Each switching status is retained even when no power is applied. Terminal 30g_f Relay Switch-on and off Conditions The terminal 30g_f relay is switched on and off underthe following conditions. Terminal 30g_f ON: • Vehicle unlocked or • Terminal R or • Change in status_contact_rear_hatch or change in status_door_contact_FAT/BFT/ FATH/BFTH Terminal 30g_f reset takes place: • On reaching the upper start capability limit (start capability limit plus bufferfor discharging in stationary mode). • When the vehicle does not assume sleep mode for 5 minutes (codeable) after sending the power down command (command for all control units to assume sleep mode) without a switch-on condition being applied. • When the vehicle is woken 10 times after switching off terminal 30g without a switch -on condition being applied. An after-running period of 2 minutes applies in this case. Terminal 30g_f OFF: • Bus activity 10 minutes after reset without a switch-on condition being applied. • Vehicle is woken 5 times without a "switch on" condition being applied. • "Signal OFF" received. Terminal 30g_f relay is switched off after 2 minutes. The terminal 30g_f relay is a bistable relay and is always in the ON state under normal conditions. It switches off the connected electric loads only in the case of fault. Once the terminal 30g_f relay has been switched off, one of the switch-on conditions is necessary in orderto switch it on again. 14 E70 Energy Management Note: Switching terminal 30g_f results in a reset ofthe instrument cluster. This means the time must be reset again. Continuous Positive As before, various electric loads are connected directly to terminal 30. The PDC control unit is connected to terminal 15. 0 r Index Explanation Definition/Function 1 IBS M onitors voltage, current and temperature 2 Vehicle battery Supplies powervia the power distribution boxes to the individual loads 3 Front power distribution box with terminal 30g relay Equipped with one relay for load shutdown (KL30g) 4 Rear power distribution box with KL30g and KL30g_f relays Equipped with two relays for load shutdown (KL30g and KL30g_f) 5 CAS 3 Responsible for controlling KL30g relay in the power distribution boxes 6 J unction Box Control unit Responsible for controlling the KL30g_f relay 7 Digital Motor Electronics Responsible for evaluating the measured data ofthe IBS and requests activation by the junction box control unit as required. When the charge status ofthe battery is low, at "terminal R OFF", the engine management additionally sends a requestto switch off terminal 30g to the CAS. 15 E70 Energy Management General Measures The terminals "load shut-down" and the terminal "interior lighting" are switched off as a general measure when the vehicle is in stationary mode. This occurs only when the vehicle is not locked and secured. These loads are shutdown immediately when the vehicle is locked and secured. This measure affects the following electric loads: Electric Loads Terminal Interior lighting (front and rear) Load shut-down after 8 minutes (immediately if locked) Footwell lighting (front and rear) Load shut-down after 8 minutes (immediately if locked) Reading light (front and rear) Load shut-down after 8 minutes (immediately if locked) Vanity mirror light Load shut-down after 8 minutes (immediately if locked) Terminal R Load shut-down 8 minutes after opening door (immedi¬ ately if locked, only on vehicles with Comfort Access) Terminal R Load shut-down after 2 minutes at poor battery charge status (immediately if locked, only on vehicles with Comfort Access) Light (switch position 2 - low beam) Load shut-down after "terminal R OFF" and door open 16 E70 Energy Management Components The energy management consists of the following components: • Combustion engine • Alternator • Vehicle battery • Intelligent battery sensor (depending on equipment) • J unction box • Engine management (power management) • Loads The most important components of the energy management system are described in the following. Intelligent Battery Sensor (IBS) The intelligent battery sensor has the same scope of functions as the intelligent battery sensor in the predecessor models.