Engine Immobiliser W/ Smart Key

DOOR LOCK: WIRELESS DOOR LOCK CONTROL SYSTEM (w/ Smart Key System): B1242: Wireless Door Lock Tuner Circuit Malfunction
B1242 - Wireless Door Lock Tuner Circuit Malfunction

DESCRIPTION

The door control receiver receives lock / unlock signals from the transmitter and sends these signals to the main body ECU via the certification ECU using the serial line.

The main body ECU then activates the door lock motor on each door in accordance with these signals.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK WIRE HARNESS (CERTIFICATION ECU - DOOR CONTROL RECEIVER)





(a) Disconnect the E84 ECU connector.

(b) Disconnect the L24 receiver 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.

2. CHECK DOOR CONTROL RECEIVER (+B TERMINAL)





(a) Measure the voltage of the connector.

Standard voltage:





NG -- REPLACE CERTIFICATION ECU
OK -- Continue to next step.

3. REPLACE DOOR CONTROL RECEIVER

(a) Temporarily replace the door control receiver with a new or normally functioning one Removal.

(b) Perform the REGISTRATION procedures.

NEXT -- Continue to next step.

4. CHECK FOR DTC

(a) Clear the DTC Wireless Door Lock Control System (w/ Smart Key System).

(b) Check if the same DTC is detected.

OK:

DTC B1242 is not output.

NG -- REPLACE CERTIFICATION ECU

OK -- END (DOOR CONTROL RECEIVER IS DEFECTIVE)