WIRELESS DOOR LOCK CONTROL SYSTEM(w/ Entry and Start 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). (example 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 CSEL 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.

  • Harness or connector

  • Door control receiver

  • Certification ECU (Smart key ECU assembly)

WIRING DIAGRAM

B265620E10

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 and wireless function performance may be affected.

  • This DTC is not detected within 10 seconds after the engine switch is turned to off from ON.

  • 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 systems are functioning properly.

    Click here

  • Before replacing the certification ECU (smart key ECU assembly), refer to the entry and start system (for Entry Function) precaution.

    Click here

PROCEDURE

  1. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    1. B299802C04

      *a

      Component with harness connected

      (Certification ECU [Smart Key ECU Assembly])

      Disconnect the M11*1 or M10*2 door control receiver connector.

      • *1: for 12 Pin Type

      • *2: except 12 Pin Type

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      G82-11 (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

      G83-5 (RCO) - Body ground

      Always

      Below 1 V → 4.5 to 5.5 V

      (Pulse generation)

      G83-17 (RDAM) - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE DOOR CONTROL RECEIVER

    Click here

    NG

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

    1. Disconnect the M11*1 or M10*2 door control receiver connector.

      • *1: for 12 Pin Type

      • *2: except 12 Pin Type

    2. Disconnect the G82 and G83 certification ECU (smart key ECU assembly) connectors.

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

      Standard Resistance

      Table 1. for 12 Pin Type

      Tester Connection

      Condition

      Specified Condition

      G83-6 (CSEL) - M11-6 (CSEL)

      Always

      Below 1 Ω

      G83-17 (RDAM) - M11-9 (DATA)

      Always

      Below 1 Ω

      G83-5 (RCO) - M11-10 (+5)

      Always

      Below 1 Ω

      M11-12 (E) - Body ground

      Always

      Below 1 Ω

      G83-6 (CSEL) - Body ground

      Always

      10 kΩ or higher

      M11-6 (CSEL) - Body ground

      Always

      10 kΩ or higher

      G83-17 (RDAM) - Body ground

      Always

      10 kΩ or higher

      M11-9 (DATA) - Body ground

      Always

      10 kΩ or higher

      G83-5 (RCO) - Body ground

      Always

      10 kΩ or higher

      M11-10 (+5) - Body ground

      Always

      10 kΩ or higher
      Table 2. except 12 Pin Type

      Tester Connection

      Condition

      Specified Condition

      G83-6 (CSEL) - M10-2 (CSEL)

      Always

      Below 1 Ω

      G83-17 (RDAM) - M10-5 (DATA)

      Always

      Below 1 Ω

      G83-5 (RCO) - M10-4 (+5)

      Always

      Below 1 Ω

      M10-1 (GND) - Body ground

      Always

      Below 1 Ω

      G83-6 (CSEL) - Body ground

      Always

      10 kΩ or higher

      M10-2 (CSEL) - Body ground

      Always

      10 kΩ or higher

      G83-17 (RDAM) - Body ground

      Always

      10 kΩ or higher

      M10-5 (DATA) - Body ground

      Always

      10 kΩ or higher

      G83-5 (RCO) - Body ground

      Always

      10 kΩ or higher

      M10-4 (+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