B2789

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

DESCRIPTION

This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) stops for 10 seconds or more.

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.
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.
* Before replacing the certification ECU (smart key ECU assembly) or immobiliser code ECU, refer to the engine immobiliser system Engine Immobilizer System (w/ Smart Key System).

HINT
When DTC B2789 and B2785 are output simultaneously, perform troubleshooting for DTC B2785 first B2785.

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 B2789 is not output.

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

OK -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

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

(a) Disconnect the C35 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the C38 ID code box (immobiliser code ECU) 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 C38 ID code box (immobiliser code ECU) connector.

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

Standard Resistance:

Text in Illustration

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

5. REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

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

NEXT -- Continue to next step.

6. CLEAR DTC

(a) 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 B2789 is not output.

NG -- REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Removal

OK -- END (ID CODE BOX [IMMOBILISER CODE ECU] IS DEFECTIVE)