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Smart Key System





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

DESCRIPTION

The certification ECU decodes the requested smart key system operation by identifying a key code based on electric waves received via the door control receiver. 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 main body ECU.)





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

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

(a) Disconnect the E58 ECU connector.





(b) Disconnect the O18 receiver connector.

(c) 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 AND REPLACE DOOR CONTROL RECEIVER (RECONFIRM DTC)

(a) Replace the receiver.

(b) Clear the DTCs and repeat the procedure to recheck for DTCs Door Lock - Smart Key System.

OK:

DTC is not output.

OK -- END (RECEIVER IS DEFECTIVE)

NG -- REPLACE CERTIFICATION ECU