B2789

MULTIPLEX COMMUNICATION: LIN COMMUNICATION SYSTEM: B2789: No Response from ID BOX
B2789 - No Response from ID BOX

DESCRIPTION

This DTC is output when LIN communication between the certification ECU and ID code box stops for 10 seconds or more.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When using the Techstream with the power switch OFF to troubleshoot:

Connect the Techstream to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the tester and vehicle begins.

HINT
DTC B2785 is output when the communication between all of the following components and certification ECU stops.

PROCEDURE

1. CLEAR DTC

(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.

NEXT -- Continue to next step.

2. CHECK FOR DTC

(a) Recheck for DTC Reading and Clearing Diagnostic Trouble Codes.

Result





B -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting
A -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ID CODE BOX)





(a) Disconnect the L15 ECU connector.

(b) Disconnect the L32 box connector.

(c) 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. CHECK HARNESS AND CONNECTOR (ID CODE BOX - BATTERY AND BODY GROUND)

(a) Disconnect the L32 box connector.





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

Standard resistance:





Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. REPLACE ID CODE BOX

(a) Temporarily replace the ID code box with a new one Removal.

(b) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.

NEXT -- Continue to next step.

6. CHECK FOR DTC

(a) Recheck for DTC Reading and Clearing Diagnostic Trouble Codes.

Result





B -- REPLACE CERTIFICATION ECU Removal

A -- END (ID CODE BOX IS DEFECTIVE)