Door Lock - Smart Key System

DOOR LOCK: SMART KEY SYSTEM: B1242: Wireless Door Lock Tuner Circuit Malfunction
B1242 - Wireless Door Lock Tuner Circuit Malfunction

DESCRIPTION

* The tuner is used as antenna for the entry and wireless door lock functions of the smart key system.

* The certification ECU decodes the requested smart key system operation by identifying a key code based on electric waves received via the tuner. The ECU then sends a command, according to the requested operation, to each ECU. (e.g. If door lock operation is requested, the ECU sends a door lock command to the body ECU.)





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - TUNER)

(a) Disconnect the D39 ECU connector.





(b) Disconnect the L11 tuner connector.





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

Resistance:





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

2. INSPECT CERTIFICATION ECU

(a) Reconnect the D39 ECU connector.





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

Voltage:





Result:





C -- REPLACE CERTIFICATION ECU

B -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A -- Continue to next step.

3. REPLACE TUNER (RECONFIRM DTC)

(a) Replace the tuner.

(b) Clear the DTC and repeat the procedure to re-check it Door Lock - Smart Key System.

OK:

DTC is output.

NG -- REPLACE CERTIFICATION ECU

OK -- END (TUNER IS DEFECTIVE)