CAN COMMUNICATION SYSTEM (for RHD), Diagnostic DTC:U1002

DESCRIPTION

• The network gateway ECU stores this DTC when no signals can be received from the ECUs that have been memorized as those connected to the WIL bus circuit.

• When the network gateway ECU receives a response signal from the ECUs connected to the WIL bus circuit, the network gateway ECU recognizes and memorizes that the ECU is connected to the WIL bus circuit. Based on this memorized data, the network gateway ECU monitors for malfunctions in the ECUs connected to the WIL bus circuit when communicating with those ECUs. If the network gateway ECU cannot receive response signals from the ECUs that have been memorized as those connected to the WIL bus circuit, the network gateway ECU determines that a malfunction exists.

• If 2 or more DTCs are output during the DTC check, one side of the CAN branch wire may be open (one side of the CANH [CAN branch wire]/CANL [CAN branch wire] of the ECU and/or sensor is open).

• For vehicles with a pre-crash intelligent headrest.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. PRECAUTION

   Note

   After turning the engine switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

   
   

   NEXT

2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL

   
   

   1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the CAN main wire and the CAN branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

   
   

   NEXT

3. CHECK CAN BUS WIRE (CAN MAIN WIRE FOR DISCONNECTION, BUS LINE FOR SHORT CIRCUIT)

   
   
   1. 

      Text in Illustration

      *a	Component with harness connected (Active Headrest Control ECU RH [Front Seat Headrest Assembly RH])
      *b	Front view of DLC3

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition Resistance: Malfunction e60-2 (CA3H) - e60-5 (CA3L) Engine switch off 54 to 69 Ω Below 53 Ω: Short in line e60-2 (CA3H) - e60-5 (CA3L) Engine switch off 54 to 69 Ω Higher than 70 Ω: Open in CAN main bus line e60-2 (CA3H) - L31-16 (BAT) Engine switch off 6 kΩ or higher Below 6 kΩ: +B short e60-5 (CA3L) - L31-16 (BAT) Engine switch off 6 kΩ or higher Below 6 kΩ: +B short e60-2 (CA3H) - e60-1 (GND) Engine switch off 200 Ω or higher Below 200 Ω: Ground short e60-5 (CA3L) - e60-1 (GND) Engine switch off 200 Ω or higher Below 200 Ω: Ground short

      Result

      Result	Proceed to
      NG Open in CAN main wire	A
      NG Short in line +B short Ground short	B
      OK	C

   
   

   B

   CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - NETWORK GATEWAY ECU) Click here

   C

   CHECK HARNESS AND CONNECTOR (NETWORK GATEWAY ECU - BATTERY AND BODY GROUND) Click here

   A

4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU RH)

   
   
   1. 

      Text in Illustration

      *a	Rear view of wire harness connector (to No. 13 Junction Connector)

      Disconnect the No. 13 junction connector.

   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition L96-3 (CANH) - L96-14 (CANL) Engine switch off 108 to 132 Ω

   
   

   NG

   CONNECT CONNECTOR Click here

   OK

5. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU RH)

   
   
   1. 

      Text in Illustration

      *a	Rear view of wire harness connector (to No. 13 Junction Connector)

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition L96-2 (CANH) - L96-13 (CANL) Engine switch off 108 to 132 Ω

   
   

   NG

   CONNECT CONNECTOR Click here

   OK

   REPLACE NO. 13 JUNCTION CONNECTOR

6. CONNECT CONNECTOR

   
   

   1. Reconnect the L96 No. 13 junction connector.

   
   

   NEXT

7. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ACTIVE HEADREST CONTROL ECU RH)

   
   
   1. 

      Text in Illustration

      *a	Rear view of wire harness connector (to Active Headrest Control ECU RH [Front Seat Headrest Assembly RH])

      Disconnect the active headrest control ECU RH (front seat headrest assembly RH) connector.

   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition e60-2 (CA3H) - e60-5 (CA3L) Engine switch off 108 to 132 Ω

   
   

   NG

   REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ACTIVE HEADREST CONTROL ECU RH (ACTIVE HEADREST CONTROL ECU RH - NO. 13 JUNCTION CONNECTOR)

   OK

   REPLACE ACTIVE HEADREST CONTROL ECU RH (FRONT SEAT HEADREST ASSEMBLY RH) Click here

8. CONNECT CONNECTOR

   
   

   1. Reconnect the L96 No. 13 junction connector.

   
   

   NEXT

9. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ACTIVE HEADREST CONTROL ECU LH)

   
   
   1. 

      Text in Illustration

      *a	Rear view of wire harness connector (to Active Headrest Control ECU LH [Front Seat Headrest Assembly LH])

      Disconnect the active headrest control ECU LH (front seat headrest assembly LH) connector.

   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition e73-2 (CA3H) - e73-5 (CA3L) Engine switch off 108 to 132 Ω

   
   

   NG

   REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ACTIVE HEADREST CONTROL ECU LH (ACTIVE HEADREST CONTROL ECU LH - NO. 13 JUNCTION CONNECTOR)

   OK

   REPLACE ACTIVE HEADREST CONTROL ECU LH (FRONT SEAT HEADREST ASSEMBLY LH) Click here

10. CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - NETWORK GATEWAY ECU)

    
    
    1. 

       Text in Illustration

       *a	Rear view of wire harness connector (to No. 13 Junction Connector)
       *b	Front view of DLC3

       Disconnect the No. 13 junction connector.

    2. Measure the resistance according to the value(s) in the table below.

       Standard Resistance
       Tester Connection Switch Condition Specified Condition L96-1 (CANH) - L96-12 (CANL) Engine switch off 200 Ω or higher L96-1 (CANH) - L31-4 (CG) Engine switch off 200 Ω or higher L96-12 (CANL) - L31-4 (CG) Engine switch off 200 Ω or higher L96-1 (CANH) - L31-16 (BAT) Engine switch off 6 kΩ or higher L96-12 (CANL) - L31-16 (BAT) Engine switch off 6 kΩ or higher

    
    

    NG

    CONNECT CONNECTOR Click here

    OK

11. CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU RH)

    
    
    1. 

       Text in Illustration

       *a	Rear view of wire harness connector (to No. 13 Junction Connector)
       *b	Front view of DLC3

       Measure the resistance according to the value(s) in the table below.

       Standard Resistance
       Tester Connection Switch Condition Specified Condition L96-3 (CANH) - L96-14 (CANL) Engine switch off 108 to 132 Ω L96-3 (CANH) - L31-4 (CG) Engine switch off 200 Ω or higher L96-14 (CANL) - L31-4 (CG) Engine switch off 200 Ω or higher L96-3 (CANH) - L31-16 (BAT) Engine switch off 6 kΩ or higher L96-14 (CANL) - L31-16 (BAT) Engine switch off 6 kΩ or higher

    
    

    NG

    CONNECT CONNECTOR Click here

    OK

12. CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU RH)

    
    
    1. 

       Text in Illustration

       *a	Rear view of wire harness connector (to No. 13 Junction Connector)
       *b	Front view of DLC3

       Measure the resistance according to the value(s) in the table below.

       Standard Resistance
       Tester Connection Switch Condition Specified Condition L96-2 (CANH) - L96-13 (CANL) Engine switch off 108 to 132 Ω L96-2 (CANH) - L31-4 (CG) Engine switch off 200 Ω or higher L96-13 (CANL) - L31-4 (CG) Engine switch off 200 Ω or higher L96-2 (CANH) - L31-16 (BAT) Engine switch off 6 kΩ or higher L96-13 (CANL) - L31-16 (BAT) Engine switch off 6 kΩ or higher

    
    

    NG

    CONNECT CONNECTOR Click here

    OK

    REPLACE NO. 13 JUNCTION CONNECTOR

13. CONNECT CONNECTOR

    
    

    1. Reconnect the L96 No. 13 junction connector.

    
    

    NEXT

14. CHECK FOR SHORT IN CAN BUS WIRES (NETWORK GATEWAY ECU)

    
    
    1. 

       Text in Illustration

       *a	Front view of wire harness connector (to Network Gateway ECU)
       *b	Front view of DLC3

       Disconnect the network gateway ECU connector.

    2. Measure the resistance according to the value(s) in the table below.

       Standard Resistance
       Tester Connection Switch Condition Specified Condition L102-13 (CA2H) - L102-12 (CA2L) Engine switch off 54 to 69 Ω L102-13 (CA2H) - L31-4 (CG) Engine switch off 200 Ω or higher L102-12 (CA2L) - L31-4 (CG) Engine switch off 200 Ω or higher L102-13 (CA2H) - L31-16 (BAT) Engine switch off 6 kΩ or higher L102-12 (CA2L) - L31-16 (BAT) Engine switch off 6 kΩ or higher

    
    

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO NETWORK GATEWAY ECU (CA2H, CA2L)

    OK

    REPLACE NETWORK GATEWAY ECU Click here

15. CONNECT CONNECTOR

    
    

    1. Reconnect the L96 No. 13 junction connector.

    
    

    NEXT

16. CHECK FOR SHORT IN CAN BUS WIRES (ACTIVE HEADREST CONTROL ECU RH)

    
    
    1. 

       Text in Illustration

       *a	Rear view of wire harness connector (to Active Headrest Control ECU RH [Front Seat Headrest Assembly RH])
       *b	Front view of DLC3

       Disconnect the headrest control ECU RH (front seat headrest assembly RH) connector.

    2. Measure the resistance according to the value(s) in the table below.

       Standard Resistance
       Tester Connection Switch Condition Specified Condition e60-2 (CA3H) - e60-5 (CA3L) Engine switch off 108 to 132 Ω e60-2 (CA3H) - L31-4 (CG) Engine switch off 200 Ω or higher e60-5 (CA3L) - L31-4 (CG) Engine switch off 200 Ω or higher e60-2 (CA3H) - L31-16 (BAT) Engine switch off 6 kΩ or higher e60-5 (CA3L) - L31-16 (BAT) Engine switch off 6 kΩ or higher

    
    

    NG

    REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ACTIVE HEADREST CONTROL ECU RH (CA3H, CA3L)

    OK

    REPLACE ACTIVE HEADREST CONTROL ECU RH (FRONT SEAT HEADREST ASSEMBLY RH) Click here

17. CONNECT CONNECTOR

    
    

    1. Reconnect the L96 No. 13 junction connector.

    
    

    NEXT

18. CHECK FOR SHORT IN CAN BUS WIRES (ACTIVE HEADREST CONTROL ECU LH)

    
    
    1. 

       Text in Illustration

       *a	Rear view of wire harness connector (to Active Headrest Control ECU LH [Front Seat Headrest Assembly LH])
       *b	Front view of DLC3

       Disconnect the headrest control ECU LH (front seat headrest assembly LH) connector.

    2. Measure the resistance according to the value(s) in the table below.

       Standard Resistance
       Tester Connection Switch Condition Specified Condition e73-2 (CA3H) - e73-5 (CA3L) Engine switch off 108 to 132 Ω e73-2 (CA3H) - L31-4 (CG) Engine switch off 200 Ω or higher e73-5 (CA3L) - L31-4 (CG) Engine switch off 200 Ω or higher e73-2 (CA3H) - L31-16 (BAT) Engine switch off 6 kΩ or higher e73-5 (CA3L) - L31-16 (BAT) Engine switch off 6 kΩ or higher

    
    

    NG

    REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ACTIVE HEADREST CONTROL ECU LH (CA3H, CA3L)

    OK

    REPLACE ACTIVE HEADREST CONTROL ECU LH (FRONT SEAT HEADREST ASSEMBLY LH) Click here

19. CHECK HARNESS AND CONNECTOR (NETWORK GATEWAY ECU - BATTERY AND BODY GROUND)

    
    
    1. 

       Text in Illustration

       *a	Front view of wire harness connector (to Network Gateway ECU)

       Connect the cable to the negative (-) battery terminal.

       Note

       When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. Disconnect the network gateway ECU connector.

    3. Measure the voltage according to the value(s) in the table below.

       Standard Voltage
       Tester Connection Switch Condition Specified Condition L102-10 (IG1) - Body ground Engine switch on (IG) 11 to 14 V

    4. Measure the resistance according to the value(s) in the table below.

       Standard Resistance
       Tester Connection Condition Specified Condition L102-4 (GND) - Body ground Always Below 1 Ω

    
    

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE NETWORK GATEWAY ECU Click here