WIRELESS DOOR LOCK CONTROL SYSTEM, Diagnostic DTC:B1242

DTC Code DTC Name
B1242 Wireless Door Lock Tuner Circuit Malfunction

DESCRIPTION

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) via CAN communication system. The certification ECU (smart key ECU assembly) sends door lock/unlock commands 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

One of the following conditions is met:


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

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

  • Door control receiver

  • Certification ECU (smart key ECU assembly)

  • Harness or connector

WIRING DIAGRAM

B006GJZE13

CAUTION / NOTICE / HINT

Note


  • When using the GTS with the engine switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start. While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

  • If the certification ECU (smart key ECU assembly) is replaced, refer to the Service Bulletin.

  • 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 and start function and wireless control function performance may be affected.

  • Check that there are no electrical key transmitter sub-assemblies in the vehicle.

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

  • 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.

  • It is necessary to perform initialization after registration of the transmitter IDs into the door control receiver if the door control receiver has been replaced.


PROCEDURE


  1. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. Disconnect the L48 door control receiver connector.

    2. Measure the voltage and resistance and check for pulses according to the value(s) in the table below.

      B006DTHC18
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      		 - -
      Standard Voltage
      Tester Connection Condition Specified Condition
      L31-19 (RDAM) - G71-18 (E) Always 11 to 14 V
      L31-18 (RCO) - G71-18 (E) Always

      Pulse generation at regular intervals

      (Below 1 V ←→ 4.5 to 5.5 V)
      Standard Resistance
      Tester Connection Condition Specified Condition
      G71-18 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE DOOR CONTROL RECEIVER Click here

    NG

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


    1. Disconnect the L31 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the L48 door control receiver connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L31-19 (RDAM) - L48-2 (DATA) Always Below 1 Ω
      L31-18 (RCO) - L48-8 (+5) Always Below 1 Ω
      L48-12 (GND) - Body ground Always Below 1 Ω
      L48-2 (DATA) or L31-19 (RDAM) - Other terminals and body ground Always 10 kΩ or higher
      L48-8 (+5) or L31-18 (RCO) - Other terminals and 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