1、MultiplexCommunicationSystem CAN CAN CommunicationnGeneral What is CAN ? CAN is an acronym that stands forController Area Network. CAN is a serial communication protocol developed by BOSCH in 1986 and standardized by (International Standards Organization)High Speed Communication of large volume data
2、Reduce amount of wire harnessReliable TransmissionAdvantage of CANCAN CommunicationnFeature Communication Speed High-speed communication (ISO 11898)ControlDriving Control SystemBody Electrical Control SystemProtocol*1CAN (ISO Standard)BEAN(TOYOTA Original)AVC-LAN(TOYOTA Original)Communication Speed5
3、00 kbps* (Max. 1 Mbps)Max. 10 kbpsMax. 17.8 kbpsCommunication wireTwist Pair WireAV signal DriveTwist Pair WireDrive TypeDifferential Voltage DriveSingle Wire Voltage DriveDifferential Voltage DriveData Length1-8 Byte (Variable)1-11 Byte (Variable)0-32 Byte (Variable)*1: Rule for data communications
4、*2: bit (bit per second)CAN CommunicationnFeature Communication Frame Same as BEAN communication, all CAN nodes (ECUs, sensors) communicate with bit signalData TypeHeaderCommunication FramePriorityData LengthAddress for Receiver ECUError Detection CodeEnd MessageDataResponse of Receive ECUCAN Commun
5、icationnFeature Communication Type Bus StyleDLC3Engine ECU (ECM)Skid Control ECUYaw Rate SensorDeceleration SensorEPS ECUSteeringAngleSensor: CAN Main Bus Line (High): CAN Sub Bus Line (High): CAN Main Bus Line (Low): CAN Sub Bus Line (Low)CAN CommunicationnFeature Communication Wire CAN uses twiste
6、d-pair wireCAN Differential Voltage DriveBEAN Single Wire Voltage DriveECUECUECUECUTwisted-pair WireHiAV Single WireHiLoLoCAN CommunicationnFeature Communication signal2.5 V3.5 VCAN HICAN LOCAN CombineOutput VoltageTime0 V2.5 V1.5 V0 VTime2.5 V1.5 V0 VTime3.5 VCAN HICAN LOCAN CommunicationnCommunica
7、tion System Diagram Case of PRIUS (NHW20)Yaw Rate SensorDeceleration SensorJunctionConnector No. 2JunctionConnector No. 1Steering Angle SensorTerminal Circuit (120 )EPS ECUSkid Control ECUHV ECUGatewayECUCAN-HCAN-LDLC3SIL: CAN Main Bus Line (High): CAN Sub Bus Line (High): CAN Main Bus Line (Low): C
8、AN Sub Bus Line (Low): Serial Communication LineBattery ECUEngine ECU(ECM)CAN CommunicationnJunction ConnectorMain Bus LineSub Bus LineJunctionConnectorSub Bus LineCAN CommunicationnTerminal CircuitDLC3EPS ECUSteeringAngleSensorJunctionConnector: CAN Main Bus Line (High): CAN Sub Bus Line (High): CA
9、N Main Bus Line (Low): CAN Sub Bus Line (Low)Battery ECUSkid Control ECUYaw Rate SensorDeceleration SensorEngine ECU(ECM)TerminalCircuitTerminalCircuitCAN CommunicationnTerminal Circuit Normal condition3.5 VTime0 V2.5 VYaw Rate SensorDeceleration SensorEngine ECU(ECM)Skid Control ECUAbsorb the Signa
10、lCAN CommunicationnTerminal Circuit With faulty resistor3.5 VTime0 V2.5 VYaw Rate SensorDeceleration SensorSkid Control ECUEngine ECU(ECM)CAN CommunicationnLocationBattery ECUSteering Angle SensorJ/C No. 1DLC3Skid Control ECUYaw Rate and Deceleration SensorHV ECUJ/C No. 2Engine ECUEPS ECUGateway ECU
11、CAN CommunicationnCommunication Frequency Both nodes have two type of communication procedures (Regularly / Event)ControlRegular (ms)EventEngine ECU (ECM) Control24 32NoneECT ECU Control32 64Sensors12 24Data Sending / Command(switch operation)Approx. 500 5000withNOTE:BEAN: 50 1000 ms (250, 500, 1000
12、)CAN CommunicationnInspection ProcedureTwo methods to check bus communication1. IT-II Tester2. DVOM1. Bus Check2. CAN Bus Line CheckCAN CommunicationnBus Check Bus Check Procedure (Communication Bus Check)Touch!CAN CommunicationnBus Check Bus Check Procedure (Communication Bus Check)Touch!CAN Commun
13、icationnBus Check Bus Check Procedure (Communication Bus Check)Touch!CAN CommunicationnBus Check Bus Check Procedure (Communication Bus Check)Touch!CAN CommunicationnBus Check Bus Check Procedure (Communication Bus Check)Engine and ECTAir SuspensionABS / VSCAir ConditionerImmobiliserSRS AirbagGatewa
14、yExitAuto DetectNow detecting. Please wait.CAN CommunicationnBus Check Bus Check Procedure (Communication Bus Check)Engine and ECTAir SuspensionABS / VSCAir ConditionerImmobiliserSRS AirbagGatewayExitCAN CommunicationnBus Check Bus Check Procedure (Communication Malfunction DTC)Touch!CAN Communicati
15、onnBus Check Bus Check Procedure (Communication Malfunction DTC)Touch!CAN CommunicationnBus Check Bus Check Procedure (Communication Malfunction DTC)Engine and ECTOKAir SuspensionOKABS / VSC1Laser CruiseOKAir ConditionerOKImmobiliserOKSRS Airbag2Gateway1Body No.2OKBody No.4OKBody No.5OKCAN Communica
16、tionnBus Check Bus Check Procedure (Communication Malfunction DTC)Engine and ECTOKAir SuspensionOKABS / VSC1Laser CruiseOKAir ConditionerOKImmobiliserOKSRS Airbag2Gateway1Body No.2OKBody No.4OKBody No.5OKDetailsExitTouch!CAN CommunicationnBus Check Bus Check Procedure (Communication Malfunction DTC)
17、Engine and ECTOKAir SuspensionOKABS / VSC1Laser CruiseOKAir ConditionerOKImmobiliserOKSRS Airbag2Gateway1Body No.2OKBody No.4OKBody No.5OKDetailsExitDTCTouch!CAN CommunicationnBus Check Bus Check Procedure (Communication Malfunction DTC)Engine and ECTOKAir SuspensionOKLaser CruiseOKAir ConditionerOK
18、ImmobiliserOKSRS Airbag2Gateway1Body No.2OKBody No.4OKBody No.5OKDetailsExit1ABS / VSCTouch!CAN CommunicationnBus Check Bus Check Procedure (Communication Malfunction DTC)Engine and ECTOKAir SuspensionOKLaser CruiseOKAir ConditionerOKImmobiliserOKSRS Airbag2Gateway1Body No.2OKBody No.4OKBody No.5OKD
19、etailsExit1ABS / VSCRetrievingNow retrieving DTCs. Please wait.CAN CommunicationnBus Check Bus Check Procedure (Communication Malfunction DTC)CurrentP Pe en nd di in ng gH Hi is st to or ry yClearSave Bus Check Function View System Bar HelpDTCDataListViewActiveTestUtilityLost Communication WithMirro
20、r Control ModuleLost Communication WithECM/PCM Current DTCLost Communication with TCMU0213U0100U01013Exit通信異常関DTC表示(”U*”、“B*”,”P*”一部）CAN CommunicationnBus Check Check communication with ECUs and sensorsEngine ECU (ECM)Yaw Rate SensorDeceleration SensorSkid Control ECUSteering Angle SensorDLC3CAN Com
21、municationnBus Check Both ECUs and sensors on CAN have self-diagnosis and communication functionEngine ECU (ECM)Yaw Rate SensorDeceleration SensorSkid Control ECUSteering Angle SensorDLC3Logic- Self-diagnosis- Communication FunctionCAN CommunicationnCAN Bus Line Check Measure the resistance value be
22、tween CANH and CANL with IG switch “OFF”DLC3Yaw Rate SensorDeceleration SensorSkid Control ECUCANHCANLEngine ECU (ECM)Resistance Value54 69 600Resistance Valuemore than 69 600Resistance Valueless than 54 600CAN CommunicationnCAN Bus Line Check Resistance value between 54 and 69 Possible causeDLC3Res
23、istance Value54 69 600Yaw Rate SensorDeceleration SensorSkid Control ECUShortEngine ECU (ECM)CAN CommunicationnCAN Bus Line Check Resistance value between 54 and 69 Inspection ItemResistance ValueBus Line ConditionCANH BATCANL BATCANH CGCANL CGmore than 1 MNo bus line malfunction if no DTC outputLes
24、s than 1 kShort between bus line groundCANLCANHCGBATInspection for short between bus line power supply/groundCAN CommunicationnCAN Bus Line Check Resistance value more than 69 (Approx. 120 ) Possible causeDLC3Yaw Rate SensorDeceleration SensorSkid Control ECUResistance Valuemore than 69 600Engine EC
25、U (ECM)OpenOpen120CAN CommunicationnCAN Bus Line Check Resistance Value more than 69 (Approx. 120 )1. Disconnect main bus line and check resistanceDLC3Yaw Rate SensorDeceleration SensorSkid Control ECUEngine ECU (ECM)OpenResistance Valueis 120 or not600120OpenDisconnect Main LineCAN CommunicationnCA
26、N Bus Line Check Resistance value more than 69 (Approx. 120 )2. Check J/C and terminal circuitJunction ConnectorCANHCANLResistance Valueis 120 or not600120Main BusCAN CommunicationnCAN Bus Line Check Resistance value more than 69 (Approx. ) Possible causeDLC3Yaw Rate SensorDeceleration SensorSkid Co
27、ntrol ECUResistance Valuemore than 69 600Engine ECU (ECM)OpenCAN CommunicationnCAN Bus Line Check Resistance value less than 54 (Approx. 0 ) Possible causeDLC3Yaw Rate SensorDeceleration SensorSkid Control ECUEngine ECU (ECM)Resistance Valueless than 54 600ShortShortCAN CommunicationnCAN Bus Line Ch
28、eck Resistance Value less than 54 (Approx. 0 ) Disconnect DLC3 Sub Bus line and check DLC3Yaw Rate SensorDeceleration SensorSkid Control ECUEngine ECU (ECM)Resistance Valuemore than 1 M 01MDisconnect DLC3 Sub Bus lineShortCAN CommunicationnCAN Bus Line Check If resistance value is , DLC3 is good Dis
29、connect J/C and check short at main bus line Yaw Rate SensorDeceleration SensorSkid Control ECUEngine ECU (ECM)Disconnect DLC3 sub bus lineShortDLC3Resistance Valueless than 54 600Disconnect Main LineCAN CommunicationnDTC Combination TableDTCOutput ECUTrouble Portion (Communication Stop)HV ECUEngine ECU (ECM)Battery ECUSkid Control ECUYaw Rate SensorGateway ECUU0100HV ECUXX XXU0111XXXXU0129XXXXU0146 XXXXU3108-594XXXXU0293Engine ECU (ECM)XXXXU1000Battery ECUXXXXU0293XXXX: OutputsX: Not output: Undetectable
