B2785

ENGINE IMMOBILIZER: ENGINE IMMOBILIZER SYSTEM: B2785: Communication Malfunction between ECUs Connected by LIN

DTC B2785 - Communication Malfunction between ECUs Connected by LIN

DESCRIPTION

This DTC is output when LIN communication from the certification ECU stops for a certain amount of time.
HINT: If this DTC B2785 is detected simultaneously with DTC B2786 , B2789 or B2287, troubleshoot DTC B2786, B2789 or B2287 first.





o: DTC is output
-: DTC is not output





WIRING DIAGRAM





INSPECTION PROCEDURE
NOTICE:
- If the certification ECU or ID code box is replaced, register the key and ECU communication ID Engine Immobilizer System.
- If the steering lock ECU or main body ECU is replaced, register the ECU code and ECU communication ID Engine Immobilizer System.

PROCEDURE

1. CHECK DTC OUTPUT
(a) Delete the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Recheck for DTCs Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- USE SIMULATION METHOD TO CHECK
A -- Continue to next step.
2. REPLACE CERTIFICATION ECU
(a) Replace the certification ECU.
NEXT -- Continue to next step.
3. ELECTRICAL KEY REGISTRATION
(a) Register the electrical key code in the certification ECU Engine Immobilizer System.
NEXT -- Continue to next step.
4. ECU COMMUNICATION ID REGISTRATION
(a) Register the ECU communication ID between the ID code box and ECM Engine Immobilizer System.
NEXT -- Continue to next step.
5. CHECK DTC OUTPUT
(a) Delete the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Recheck for DTCs Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- END
A -- Continue to next step.
6. REPLACE MAIN BODY ECU
(a) Replace the main body ECU.
NEXT -- Continue to next step.
7. ECU CODE REGISTRATION
(a) Register the ECU code between the ECUs connected by LIN communication Engine Immobilizer System.
NEXT -- Continue to next step.
8. CHECK DTC OUTPUT
(a) Delete the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Recheck for DTCs Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- END
A -- Continue to next step.
9. REPLACE STEERING LOCK ECU
(a) Replace the steering lock ECU.
NEXT -- Continue to next step.
10. ECU CODE REGISTRATION
(a) Register the ECU code between the ECUs connected by LIN communication Engine Immobilizer System.
NEXT -- Continue to next step.
11. CHECK DTC OUTPUT
(a) Delete the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Recheck for DTCs Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- END
A -- REPLACE ID CODE BOX