Table of Contents E70 Voltage Supply and Bus Systems Workbook Subject Page E70 Voltage Supply . 5 Overview of System Components.6 Vehicle Battery .6 Distribution Box (on battery).6 Energy Management .7 Bus Systems . 10 New Bus Systems on the E70.10 Diagnosis CAN .11 Location of D-CAN Connector .11 FlexRay .12 FlexRay in the E70.13 MOST Bus .14 MOST Users.14 MOST Access .14 Car Access System 3 (CAS3) .17 History of the Car Access System .17 Functional Overview .17 Electronic Vehicle Immobilizer 3 (EWS 3) .18 Electronic Vehicle Immobilized (EWS 4).18 Design of EWS 4 .18 Start Enable through EWS .19 Data Transmission .19 Initial Print Date: 12/06 Revision Date: Table of Contents Subject Page Secret Key.19 Gearbox Enable.20 Start Value Matching .20 Emergency Release.20 Vehicle Data Storage .21 Data for Condition-based Service.21 Manual Update of CBS Data.21 Manual Update of Fault Memory Data.21 Control Unit Replacement.21 Table of Contents Subject Page 4 E70 Voltage Supply and Bus Systems Workbook Voltage Supply and Bus Systems Model: E70 Production: From Start of Production After completion of this module you will be able to: • Describe changes to the E70 Voltage Supply Systems • Understand the Bus Systems as applied to the E70 • Understand the new D-CAN and FlexRay E70 Voltage Supply With regard to voltage supply on the E70, much of the vehicle is configured in a similar mannerto the E9X vehicles. With increases in technology, there is an ever-increasing load on the electrical system. As with every new model, the power supply system becomes more significant. In the E70, there are two power distribution boxes. The front distribution box (2) is below the glovebox and the rear power distribution box(l) is on the right hand side of the luggage compartment. The illustration above shows the layout of the primary power supply system components. Also, there is a distribution box on the battery which contains large capacity fuses. E70 Voltage Supply and Bus Systems Workbook 5 6 E70 Voltage Supply and Bus Systems Workbook Overview of System Components The power supply system of the E70 consists of the following components: • Vehicle battery • Distribution box on the battery • Rear distribution box on the right-hand side ofthe luggage compartment • Battery cables • Front distribution box behind the glove compartment • J unction box control unit • E-box engine compartment • J ump start connection point • Alternator. The most important new features/changes to the power supply system in the E70 are described below. Vehicle Battery The vehicle battery is installed in the luggage compartment floor. The vehicle batteries are AGM type, and depending upon equip¬ ment, they are either 70 Ah or 90 Ah. Distribution Box (on battery) The distribution box in the luggage compartment ofthe E70 is mounted directly on the vehicle battery. The rear distribution box on the battery is secured on the vehicle battery by means of a metal tab. The metal tabs must be pressed downward and outward in order to release the distribution box. The distribution box on the battery is equipped with fuses for the following electric loads: • E lectrical auxiliary heater (100 A) • Valvetronic or common rail system (80 A) • Intelligent battery sensor IB S • Reserve • Front distribution box (250 A) • Rear distribution box (100 A) • Large electric fan 850 W (100 A) • Reserve. The distribution box on the battery should be replaced only as a complete unit. The fuses are integrated as a complete unit in the housing ofthe distribution box on the battery. The fuses differ in terms of their power rating. The distribution box additionally contains the power supplyforthe BS. Note: The connectors are color coded and mechanically coded to avoid confusion. These are high power connections, therefore always ensure correct contacting! When replacing or working on the distribution box, always make sure the plug connections and, above all, that the screw connec¬ tions are secured properly. Connection between battery terminal and distribution box =15 Nm. Distribution Box (on battery) Energy Management The E70 is equipped with Advanced Power Management. This simply means that the power management system includes the Intelligent Battery Sensor (IBS). M uch of the system functions the same as the E90 on which it is based. Index Explanation Index Explanation 1 Advanced Power Management 7 Electrical loads 2 Idle speed boost 8 Electrical system and battery diagnosis 3 Engine 9 BMW Diagnostic System 4 Charging voltage target value 10 Intelligent Battery Sensor 5 Alternator 11 Battery Data 6 Electrical load reduction E70 Voltage Supply and Bus Systems Workbook 7 8 E70 Voltage Supply and Bus Systems Workbook Workshop Exercise - Power Supply Using the instructor designated vehicle and the ETM's in WebTIS, locate the relays in the front & rear power distribution boxes. Fill in the chart at the right denoting the relay designation and whether or not it is soldered to the PC board. Relay Designation Soldered Yes Exercise - PowerSupply \S_ Continue with the exercise using the front power distribution box. Relay Designation Soldered E70 Voltage Supply and Bus Systems Workbook 9 10 E70 Voltage Supply and Bus Systems Workbook 1 HSJSB TPM SEN iiUi &VFA 53FA ASF £■ E-wr a I I Jl> II JBI JiB I IJI IJI IJIIJE i ■ j i i j iiaii 1 ■ i ii i n iji i i ■ neiiFnni . m m iii ■■ j | ■ m ■ ibi ii gj 7 KldlildUJUJ kI New Bus Systems on the E70 The bus network on the E70 is built upon the foundation from the E90. Many of the bus systems have been carried over. As far as the E70 bus systems are concerned, there are two new systems not previously used: • D-CAN - This is the Diagnosis CAN which will be phased into all models from this point. • FlexRay- FlexRayis currently used only on the Vertical Dynamics Management System (VDM). Diagnosis CAN After connecting a BMW diagnostic system, the gateway (junction box control unit) places the requests of the BMW diagnostic system on the internal buses. The responses undergo the same process in opposite direction. In future, a new communication protocol will be used for diagnosis. The D-CAN will replace worldwide the previous diagnostic inter¬ face and its protocol which is based on KWP 2000 (Keyword Protocol 2000). The reason for the changeover is a new legal requirement in the USA requiring that all vehicles be equipped with the D-CAN as from model year 2008. The transitional phase will begin in September 2006. This modification will then be phased-in on all BMW models. In order to connect diagnostic equipment to a vehicle equipped with D-CAN, only the OPS orOPPS can be used in conjunction with the correct cable shown below. Location of D-CAN Connector The diagnosis socket is located underthe dashboard on the driver's side in the same location as previous diagnostic connectors. D-CAN support with the diagnostic head is technically not possible. The following interfaces can be used: • OPS • OPPS OBD access in the vehicle will remain unchanged. The pin assignments are as follows: • 16 =Terminal 30 • 5 =Terminal 31 •14+6 = Communication connections The diagnosis socket is located underthe dashboard on the driver's side. The cable should have the appropriate "CAN Included" markings. c an included l/ace in G ftp wry L A E70 Voltage Supply and Bus Systems Workbook 11 12 E70 Voltage Supply and Bus Systems Workbook FlexRay Up until now, the CAN bus format has provided the necessary speed required for today's vehicle systems. From this point on, many of the new features and systems will require a more robust network with much higher communication speeds. Therefore, in 1999, the FlexRay consortium was founded by BMW AG, Philips, Motorola (Freescale) and Daimler Chrysler AG. This consortium set forth developing innovative communication technology for the future of the automobile. Since 1999, the FlexRay consortium was joined by additional partners including GM, Ford, Mazda, Bosch, and Siemens VDO. Soon after many other automotive industry concerns have signed on allowing FlexRay to become an industrial standard. lifr LH-r lisJ h | IABI !- i- if • I.-ii -• Gegelopment Member ■Ji Associate Member ,, 1 j la ■ ju 'lUJati “■ 0 * 'll KVUKJkfl,V Hia, wgTtfFig fynn I Inc'njnlcf 1 nyTi|ji Rcr-euCi E?MW Giuuij Dclptn Dj-inlSrChtiffillfir ■ . . Philips General Wotora rinrw^ K.n± SMnr Go NIH^N „ FrE'C-scnl-n Sc-micantiuctQr 1 >nl lental ■ cq„V^ IWsACSfiCo lycu Fa^d PSA FfLviifli Cliraon MUL Un i!i ■ niihi l.l.T iM ll LL-rrJL.-a 4cm ChESFnE 9vf4mAE Lmr- Ji.. i i i> i l il Flexray, with a communication speed of 10 Mbits/second,far exceeds the current CAN based systems at 500 Kbits/second. In addition to speed, FlexRay offers efficient "real time" capabilities. The following outlines the advantages of FlexRay: • High bandwidth (10 M bits£ compared to 0.5 M bits/s of the CAN) • Deterministic (= real-time capabilities) data transmission • Reliable data communication • Supports system integration • Standard in automotive industry FlexRay in the E70 Currently, the only system on the E70 which uses the FlexRay bus system is the Vertical Dynamics Management (VDM). This system is similarto the EDC system known from existing vehicle. The use of FlexRay will be expanded in future models. M any powertrain and chassis systems will adopt this format in order to be compatible with the requirements of future systems. For more information on FlexRay and VDM, referto the Chassis Dynamics section of this workbook. E70 Voltage Supply and Bus Systems Workbook 13 14 E70 Voltage Supply and Bus Systems Workbook MOST Bus MOST Users In the E70, the MOST but is used forthe components in informa¬ tion/communication systems. The CCC, M-ASK orthe CHAM P is used as the master control unit. Other bus users may be: • CD changer/DVD changer • Top-HiFi amplifier • Satellite tuner SDARS, IBOC (U.S only) • Telephone • Head-up display HUD The following overview shows a possible equipment configuration. MOST Access As on all vehicles equipped with a MOST bus system, direct MOST access is also provided on the E70. The direct MOST access is located on the right hand side under the dashboard in the vehicle interior. A cover provides direct access to the MOST. The two connectors are then plugged together. The OP S/OP PS can now be connected to the connector as usual. The two connectors must be removed from the holder secured on the cover. E70 Voltage Supply and Bus Systems Workbook 15 16 E70 Voltage Supply and Bus Systems Workbook Car Access System 3 ► Index Explanation Index Explanation 1 Hood contact switch 8 Terminal 15 2 Car Access System 3 9 Electronic Outer Door Handle Module 3 Digital Motor Electronics 10 Telematics Control Unit 4 Intelligent Battery Sensor 11 START-STOP Button 5 Starter 12 Central Lock Button 6 J unction Box Control Unit 13 Brake Light Switch 7 Identification Transmitter 14 Dynamic Stability Control Car Access System 3 (CAS3) The Car Access System now features the 3rd generation of control units. The electronic vehicle immobilizer 4 (EWS 4) is also used in connection with the Car Access System 3. The previous functions of the electronic vehicle immobilizer 3 have been retained. The Car Access System 3 can therefore be operat¬ ed together with the electronic vehicle immobilizer 3 or 4. The digital motor electronics and the Car Access System 3 are incorporated in the overall electronic vehicle immobilizer system in the E70. In addition, the electronic transmission control is used as a further immobilizer in the E70.The electronic vehicle immobilizer 4 improves the anti-theft properties of the vehicle. A longer cryptic code is used for the data exchange. The cryptic code provides the enable to start the engine. The Car Access System 3 is backwards compatible with the Car Access System 2. This means the functions of the Car Access System 2 are also included in the Car Access System 3. The electronic vehicle immobilizer 3 orthe electronic vehicle immobilizer 4 is used depending on the engine installed and the associated digital engine management. The table below shows the assignment of the engine management to the respective electronic vehicle immobilizer. Vehicle Launch Date Engine Engine Management EWS Function E70 10/06 N62B4801 ME9.2.3 EWS 3 E70 10/06 N52B30O1 MSV80 EWS 4 History of the Car Access System The Car Access System was used forthe first time in the E65 (03/2002). It has undergone continuous further development and has been successively introduced in various BMW models. Functional Overview The Car Access System 3 is responsible for many functions, including the masterforthe following functions: • Central locking • Power windows • Panoramic glass roof • Comfort Access The Car Access System 3 enables or interrupts the execution of the aforementioned functions. The control units which execute the functions are: Control units which execute functions J unction Box Control unit (| BE) Central Locking Footwell Module (FRM) PowerWindows Roof Functions Center (FZD) Panoramic Glass Roof Comfort Access (CA) Comfort Access Further functions are integrated in the Car Access System 3. They are: • Terminal control • Electronic vehicle immobilizer4 • Vehicle data storage E70 Voltage Supply and Bus Systems Workbook 17 18 E70 Voltage Supply and Bus Systems Workbook Electronic Vehicle lmmobilizer3 (EWS 3) The familiar functions of the previous EWS 3 system have been retained. The CAS 3 system is integrated in the system network via the K-CAN. The vehicle key data are read into the Car Access System 3 via the key slot. Pin 20 is used in connection with the Car Access System 3. The enable code is signalled to the digital motor management via this pin. The Car Access System 3 contains the start relay that is activated by means of an integrated circuit. The integrated circuit is informed via a separate line (A_S_Start) that the digital engine electronics is ready to start. Furthermore, the start procedure is terminated via the A_S_Start line if the engine does not start up because, for example, there is a fault in the PT-CAN system. Data transmission is unidirectional. Electronic Vehicle Immobilized (EWS 4) The electronic vehicle immobilizer 4 is an immobilizer system that prevents unauthorized engine start. It was used for the first time in the CAS 3 system in the E92. The EWS 4 system uses a new, modern encryption system. A 128 bit long secret key is assigned to each vehicle and stored in the BMW database. This secret key is known only to BMW. The secret key is programmed and locked in the Car Access System 3 and in the digital engine management. 0 nee entered in the control unit, the secret key can no longer be changed, deleted or read. This therefore means that each control unit is assigned to a specific vehicle. The electronic vehicle immobilizer 4 operates with bidirectional and redundant data transmission. The K-CAN (CAN protocol) and CAS-bus (K-bus protocol) are used forthis purpose. Pin 30 of the CAS 3 system serves as the connection to the CAS-bus. The redundant data transmission enables operation of the elec¬ tronic vehicle immobilizer even if a bus system fails due to a defect. Design of EWS 4 The vehicle immobilizer consists of the identification transmitter which identifies itself to the vehicle and therefore to the Car Access System 3. The Car Access System 3 exchanges data via the CAS- bus with the digital motor electronics and thus cancels the immobilizerfunction. The software for the electronic vehicle immobilizer as well as the enable for the starter is resident in the CAS 3. The digital engine management is responsible for issuing the enable for the ignition and fuel injection. The gearbox functions are enabled by the electronic transmission control. The remote control orthe identification transmitter must be identified as matching the vehicle before the electronic vehicle immobilizer issues the start enable. This already takes place before a vehicle is unlocked. A renewed check (authentication) must be performed as soon as an attempt is made to start the engine. The check establishes whether the remote control matches the vehicle orthe identifica¬ tion transmitter is located in the vehicle interior. The vehicle can be started if the check is successful. Authentication starts with the status "Terminal 15 ON". Note: The start enable can be given only by a remote control matching the vehicle ora suitable identification transmitter. Start Enable through EWS The start procedure is enabled by means of a special request and response procedure known as challenge-response. As from "Terminal 15 ON", the digital engine management sends an encrypted random numberto the CAS 3.The DME (ECM) control module generates the random number in a random number generator. From this random number together with its secret key, the CAS 3 system calculates a response and sends it to the DME. In the meantime, the digital engine management calculates the expected response from the random number with its secret key. The CAS 3 system and the DM E use the same secret key and algorithm forthe calculation. The electronic vehicle immobilizer is cancelled if the value which the CAS 3 sends to the digital engine management agrees with the value calculated by the engine management. The engine can now be started. Note: As from "Terminal 15 ON", a cyclic query (challenge- response) is performed as long as the engine is notyet running. A fault code is entered in the CAS 3 if there is no query from the digital engine management approxi¬ mately 10 seconds afterthe start of the request. Data Transmission Data transmission is redundant via the bus systems. The signal from the DM E reaches the CAS 3 via the K-CAN and the CAS-bus. The DME, however, is connected to the PT-CAN. For this reason, the signal is sent via the gateway of the junction box control unit to the K-CAN. The runtime of the signals via the bus systems is of no significance as the signal that reaches the DM E first is used forthe electronic vehicle immobilizer. The authentication is repeated in response to following events: • Transmission and response time exceeded • Transmission problems • Response with the secret security code incorrect (e.g. incorrect secret key due to control unit from another vehicle). S ec ret Key The control units are assigned a secret key on the assembly line. This secret key is generated from a random number. The secret key is valid fora pair of control units and linked to the specific vehicle. This means that one pair of control units receives the same secret key. Once the secret key has been entered, the control unit is locked. From this point on, the control unit is permanently tied to this secret key and the vehicle. The CAS 3 and the digital motor electronics form one pair of control units. Note: S ince the control units are assigned to the specific vehicle, replacement with a unit from another vehicle is not possible. When replacing a control unit, the new control unit must be ordered from BMW. Matching of the control units to each other is no longer necessary. E70 Voltage Supply and Bus Systems Workbook 19 20 E70 Voltage Supply and Bus Systems Workbook Gearbox Enable The enable is based on a procedure similar to that used for EWS 3. As from "Terminal 15 ON", the CAS 3 sends encrypted individual codes to the electronic transmission control. The electronic trans¬ mission control deciphers and checks these individual codes. If the check is successful, the gearbox control unit will enable the gearbox functions. The electronic gearbox control unit forms a pair of control units together with the CAS 3. Start Value Matching A start value matching procedure between the CAS 3 and the electronic transmission control is performed on the assembly line. As part of this procedure, the CAS 3 transfers in encrypted form an individual code to the electronic transmission control. Consequently, the electronic transmission control knows the indi¬ vidual code and can check whetherthe gearbox functions can be enabled. Emergency Release The parking lock cannot be released in the event of a defect or data transmission error. Forthis reason, the E70 features a mechanical emergency release facility for the parking lock. A handle for the emergency release of the parking lock is located in the luggage compartment. This handle must be plugged in under the left cup holder, turned through 90° and pushed down. The gearbox is released as soon as the handle has been locked in position. The vehicle can now be towed but not driven. Note: The handle must remain locked in position while the vehicle is being towed. The parking lock will engage if the handle is removed while the vehicle is being towed. This could cause an accident in unfavorable towing situations. Vehicle Data Storage The Car Access System 3 stores the following vehicle data: • Personal Profile, the Car Access System 3 stores data for the Personal Profile • Vehicle order, the vehicle order is stored in the footwell module • Redundant data storage for instrument cluster • Data for condition-based service CBS • Authentication for diagnosis access to vehicle Data for Condition-based Service The data for condition-based service are stored and transferred to the remote control. This data can be read out via the key reader for service purposes. The data for the condition-based service are updated during vehi¬ cle operation. The data in the fault code memory are also updated during vehicle operation. The conditions are: • "Terminal 15 ON", Speed above 50 km/h and below 30 km/h • The data are updated after covering a distance of 10 km and at a speed below 30 km/h. ■ M anual U pdate of C B S Data The procedure for transferring current data to the remote control during servicing is as follows: • Insert remote control in its holder • Press and hold center-lock button and select "terminal 15 ON" with the STARTSTOP button. • After 15 s the CBS data will have been transferred to the remote control. • Read out remote control. Manual Update of Fault Memory Data The procedure for transferring current data to the remote control during servicing is as follows: • Press and hold center-lock button • Insert remote control in its holder • Select "Terminal 15 ON" with the START-STOP button • The fault code memory data are transferred to the remote control after 15 seconds. • Read out remote control. Control Unit Replacement A defect in the control units belonging to the EWS represents a challenge forthe Service technician. Since a defective control unit cannot be replaced by control units from other vehicles particular care is necessary when performing the diagnostic procedure. A defective control unit can be ordered through spare part channels. However, it is important to bear in mind that the digital engine management and the CAS 3 were supplied already coded to the vehicle. This has the advantage that only the control unit is replaced and the matching procedure with the electronic vehicle immobilizer is not necessary. There is no point in ordering a control unit to be kept in stock as the secret key is assigned to the control unit and the vehicle. A matching procedure is necessary for the electronic transmission control after replacement. As part of this procedure, the CAS 3 transfers the individual code to the electronic transmission control. Note: The matching procedure can take several minutes. E70 Voltage Supply and Bus Systems Workbook 21 22 E70 Voltage Supply and Bus Systems Workbook Classroom Exercise - Review Questions 5. On the E70, which system incorporates the new FlexRay technology? (C ircle those that apply) 1. Which of the following devices is NOT compatible with D- CAN equipped vehicles? (Cross out those not applicable) VDM HUD CCC AS DSC ARS FRM DME Which of the following test cables is compatible with a D-CAN equipped vehicle? (Circle those that apply) Circle the bus systems which have NOT been in use prior to the introduction ofthe E70? LIN byteflight MOST K-CAN D-CAN BSD PT-CAN F-CAN FlexRay Lo-CAN What is the communication speed ofthe FlexRay system? (circle the applicable answer) 10 Mbits/s 500K/bits/sec 22.5 Mbits/sec The D-CAN signal wires are incorporated into the OBD connector at pins: (C ircle the applicable answer) 5 and 16 16 and 14 5 and 6 14 and 6 The CAS-bus connects: (circle the applicable answer) DME, CAS 3 and J B DME, EGS and CAS 3 EGS, GWS and DWA EGS, J B and FRM The CAS 3 system is the master for which of the following functions: (Circle those that apply) Central locking PowerWindows Panorama Roof Comfort Access On the E70,the KL30g_f relay is located: (Circle those that apply) In the front power distribution box In the rear power distribution box In the FRM In the CCC