WIRELESS DOOR LOCK CONTROL SYSTEM, Diagnostic DTC:B1242

DTC Code DTC Name
B1242 Wireless Door Lock Tuner Circuit Malfunction

DESCRIPTION

The door control receiver is used to receive radio waves related to the entry functions of the electrical key transmitter sub-assembly. The certification ECU (smart key ECU assembly) decodes the requested electrical key transmitter sub-assembly operation by identifying a key code based on the radio waves received via the door control receiver. The door control receiver receives a signal from the electrical key transmitter sub-assembly and sends signals to the main body ECU (multiplex network body ECU) through the certification ECU (smart key ECU assembly). (ex. if a door lock operation is requested, the certification ECU (smart key ECU assembly) sends a door lock command to the main body ECU (multiplex network body ECU)).

DTC No. Detection Item DTC Detection Condition Trouble Area
B1242 Wireless Door Lock Tuner Circuit Malfunction

  • Short in RDAM to ground between the certification ECU (smart key ECU assembly) and door control receiver.

  • Short in RDAM to ground when RCO (5 V) output from the ECU is off.

  • Wire harness or connector

  • Door control receiver

  • Certification ECU (smart key ECU assembly)

WIRING DIAGRAM

A01UDCSE01

CAUTION / NOTICE / HINT

Note


  • When replacing or inspecting the door control receiver and wire harness, do not change the position or length of the wire harness. If the wire harness is too close to the door control receiver, entry (w/ Entry Function) and wireless function performance may be affected.

  • This DTC is not stored within 10 seconds of the engine switch being turned from on (IG) to off.

  • The wireless door lock control system uses the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the wireless door lock control system after confirming that the communication system is functioning properly.

    Click here

  • When replacing the door control receiver, read the transmitter IDs (tire pressure warning system) stored in the old ECU using the GTS and write them down before removal (for 12 Pin Type).

    Click here

  • It is necessary to perform initialization () after registration ( Click here) of the transmitter IDs into the door control receiver if the door control receiver has been replaced (for 12 Pin Type).

PROCEDURE


  1. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. Disconnect the K17*1 or K18*2 door control receiver connector.


      • *1: for 12 Pin Type

      • *2: for 5 Pin Type

      A01UDTTC11
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly)

      		 - -

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G22-11 (E) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      G21-18 (RCO) - G22-11 (E) Always

      Below 1 V → 4.5 to 5.5 V

      (Pulse generation)
      G21-20 (RDAM) - G22-11 (E) Always 11 to 14 V
      Result
      Result Proceed to
      OK A
      NG (for 5 Pin Type) B
      NG (for 12 Pin Type) C

    B

    REPLACE DOOR CONTROL RECEIVER Click here

    C

    REPLACE DOOR CONTROL RECEIVER Click here

    A

  2. CHECK HARNESS AND CONNECTOR (DOOR CONTROL RECEIVER - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) AND BODY GROUND)


    1. Disconnect the G21 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the K17*1 or K18*2 door control receiver connector.


      • *1: for 12 Pin Type

      • *2: for 5 Pin Type

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

      Standard Resistance
      for 12 Pin Type
      Tester Connection Condition Specified Condition
      G21-20 (RDAM) - K17-9 (DATA) Always Below 1 Ω
      G21-18 (RCO) - K17-10 (+5) Always Below 1 Ω
      G21-20 (RDAM) or K17-9 (DATA) - Body ground Always 10 kΩ or higher
      G21-18 (RCO) or K17-10 (+5) - Body ground Always 10 kΩ or higher
      for 5 Pin Type
      Tester Connection Condition Specified Condition
      G21-20 (RDAM) - K18-5 (DATA) Always Below 1 Ω
      G21-18 (RCO) - K18-4 (+5) Always Below 1 Ω
      G21-20 (RDAM) or K18-5 (DATA) - Body ground Always 10 kΩ or higher
      G21-18 (RCO) or K18-4 (+5) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR