LIN Communication System

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

DTC B2789 - No Response from ID BOX

DESCRIPTION

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

WIRING DIAGRAM

INSPECTION PROCEDURE
NOTE: When using Techstream with the ignition switch off to troubleshoot:

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

PROCEDURE

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

(a) Disconnect the D40 and D31 connectors.
(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.
2. CHECK ID CODE BOX (IMMOBILISER CODE ECU)

(a) Disconnect the D31 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 (IMMOBILISER CODE ECU)
(a) Replace the ID code box (immobiliser code ECU) with a new one.
(b) Delete the DTC.
NEXT -- Continue to next step.
4. CHECK FOR DTC
(a) Recheck for DTC.
Result:

B -- REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
A -- END