B2602

STEERING COLUMN: POWER TILT AND POWER TELESCOPIC STEERING COLUMN SYSTEM: B2602: Key Unlock Warning Switch Circuit Malfunction

DTC B2602 - Key Unlock Warning Switch Circuit Malfunction

DESCRIPTION

The multiplex tilt and telescopic ECU uses signals from the transponder key ECU to operate the auto away function or auto return function. This DTC is output when the ignition switch is turned to ACC, ON or START, but the transponder key ECU sends an off signal.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM (UNLOCK WARNING SWITCH)
(a) Check the Data List for proper functioning of the unlock warning switch.

Multiplex tilt and telescopic ECU





OK:
ON (Communication is normal) appears on the screen.
OK -- REPLACE MULTIPLEX TILT AND TELESCOPIC ECU
NG -- Continue to next step.
2. INSPECT UNLOCK WARNING SWITCH




(a) Remove the unlock warning switch.
(b) Measure the resistance of the switch.
Standard resistance:






NG -- REPLACE UNLOCK WARNING SWITCH
OK -- Continue to next step.
3. CHECK TRANSPONDER KEY ECU




(a) Measure the voltage of the ECU.
Standard voltage:






NG -- REPLACE TRANSPONDER KEY ECU
OK -- Continue to next step.
4. CHECK WIRE HARNESS (ECU - SWITCH)




(a) Disconnect the T13 ECU connector.
(b) Disconnect the U1 switch connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.
5. CHECK WIRE HARNESS (SWITCH - BODY GROUND)




(a) Disconnect the U1 switch connector.
(b) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- REPLACE MULTIPLEX TILT AND TELESCOPIC ECU