B2785
NETWORKING: LIN COMMUNICATION SYSTEM: B2785: Communication Malfunction between ECUs Connected by LIN
B2785 - Communication Malfunction between ECUs Connected by LIN
DESCRIPTION
The certification ECU (smart key ECU assembly) intermittently monitors the LIN communication bus between the components related to certification. DTC B2785 is stored when a malfunction in the LIN communication bus between the components related to certification is detected continuously 3 times.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
* When using the Techstream with the ignition switch off to troubleshoot:
Connect the Techstream to the vehicle and turn a courtesy light switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins.
* Before replacing the certification ECU (smart key ECU assembly), immobiliser code ECU or steering lock ECU, refer to the engine immobiliser system Engine Immobilizer System (w/ Smart Key System).
HINT
* When DTC B2785 and a LIN communication stop DTC are output simultaneously, first perform troubleshooting for DTC B2785. Then perform troubleshooting for the LIN communication stop DTC.
* When DTC B2785 and B2287 are output simultaneously, perform troubleshooting for DTC B2785 first.
PROCEDURE
1. CLEAR DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
2. CHECK FOR DTC
(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
OK:
DTC B2785 is not output.
NG -- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - POWER SOURCE CONTROL ECU, ID CODE BOX AND STEERING LOCK ECU)
OK -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting
3. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - POWER SOURCE CONTROL ECU, ID CODE BOX AND STEERING LOCK ECU)
(a) Disconnect the C35 certification ECU (smart key ECU assembly) connector.
(b) Disconnect the C43 power source control ECU connector.
(c) Disconnect the C38 ID code box (immobiliser code ECU) connector.
(d) Disconnect the C18 steering lock actuator assembly (steering lock ECU) connector.
(e) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CLEAR DTC
(a) Disconnect the C43 power source control ECU connector.
(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
5. CHECK FOR DTC
(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
OK:
DTC B2785 is not output.
NG -- REPLACE POWER SOURCE CONTROL ECU Removal
OK -- Continue to next step.
6. CLEAR DTC
(a) Disconnect the C18 steering lock actuator assembly (steering lock ECU) connector.
(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
7. CHECK FOR DTC
(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
OK:
DTC B2785 is not output.
NG -- REPLACE STEERING LOCK ACTUATOR ASSEMBLY (STEERING LOCK ECU) Disassembly
OK -- Continue to next step.
8. CLEAR DTC
(a) Disconnect the C38 ID code box (immobiliser code ECU) connector.
(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
9. CHECK FOR DTC
(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
OK:
DTC B2785 is not output.
NG -- REPLACE ID CODE BOX (IMMOBILISER CODE ECU) Removal
OK -- REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Removal