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 (immobilizer code ECU) stops for 10 seconds or more.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.
* If the certification ECU (smart key ECU assembly) is replaced, register the key Engine Immobilizer System.
* If the ID code box (immobilizer code ECU) is replaced, register the ECU code and ECU communication ID Engine Immobilizer System.
* When using the Techstream to troubleshoot with the power switch off:
Connect the Techstream to the DLC3, and turn the courtesy switch on and off at 1.5-second intervals until communication between the Techstream and vehicle begins.

PROCEDURE

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

(a) Disconnect the H22 ID code box (immobilizer code ECU) 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.

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

(a) Disconnect the H1 certification ECU (smart key ECU assembly) connector.

(b) 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.

3. REPLACE ID CODE BOX (IMMOBILIZER CODE ECU)

(a) Replace the ID code box (immobilizer code ECU) Removal.

NEXT -- Continue to next step.

4. CHECK DTC OUTPUT

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

(b) Recheck for DTCs.

OK:

DTC B2789 is not output.

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

OK -- END (ID CODE BOX (IMMOBILIZER CODE ECU) WAS DEFECTIVE)