B1242 - Wireless Door Lock Tuner Circuit Malfunction

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What does this mean?

B1242 Possible Causes

  • Faulty Door Control Receiver
  • Door Control Receiver harness is open or shorted
  • Door Control Receiver circuit poor electrical connection
  • Faulty Multiplex Network Body ECU

How do I fix code B1242

    Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

Cost of diagnosing the B1242 code

    Labor: 1.0

    The cost of diagnosing the B1242 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.

B1242 Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

B1242 Meaning

The door control receiver is used to receive electrical waves relating to the entry functions of the smart access system with push-button start (for Entry Function). The certification ECU (smart key ECU assembly) decodes the requested smart access system with push-button start (for Entry Function) operation by identifying a key code based on the electric waves received via the door control receiver. The door control receiver receives a signal from the door control transmitter and sends signals to the main body ECU (cowl side junction block LH) through the certification ECU (smart key ECU assembly). The certification ECU (smart key ECU assembly) then sends a command, according to the requested operation, to each ECU (ex. if door lock operation is requested, the certification ECU (smart key ECU assembly) sends a door lock command to the main body ECU).
OBDII Code B1242 - Wireless Door Lock Tuner Circuit Malfunction - Engine-Codes.com

B1242 More Information

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B1242 Information for specific makes

  • B1242 LEXUS Wireless Door Lock Tuner Circuit Malfunction
  • B1242 SCION Wireless Door Lock Tuner Circuit Malfunction
  • B1242 TOYOTA Wireless Door Lock Tuner Circuit Malfunction

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