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 relating 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 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). 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 (multiplex network body ECU)).

DTC No. DTC Detection Condition Trouble Area
B1242

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

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

  • Harness or connector

  • Door control receiver

  • Amplifier antenna assembly

  • Certification ECU (Smart key ECU assembly)

WIRING DIAGRAM

A01FFBDE01

INSPECTION PROCEDURE

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, smart and wireless function performance may be affected.

  • Before performing the inspection, check that there are no problems related to the CAN communication system Click here.

  • When replacing the certification ECU (smart key ECU assembly) or electrical key transmitter sub-assembly, refer to the Service Bulletin.

  • 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 Click here.

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

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

  • When using the GTS with the engine switch off to troubleshoot:

    Connect the GTS to the DLC3 and turn a courtesy light switch on and off at 1.5-seconds intervals until communication between the GTS and vehicle begins.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B1242 is not output.

    NG

    CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. A01FGQ7E02
      Text in Illustration
      *A for LHD
      *B for RHD
      *a

      Component with harness connected

      (Certification ECU [Smart Key ECU Assembly])

      Disconnect the T32*1 or T33*2door 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
      A34-11 (E) - Body ground Always Below 1 Ω

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

      Standard Voltage
      for LHD
      Tester Connection Condition Specified Condition
      T2-5 (RCO) - A34-11 (E) Always

      Below 1 V → 4.5 to 5.5 V

      (Pulse generation)
      T2-17 (RDAM) - A34-11 (E) Always 11 to 14 V
      for RHD
      Tester Connection Condition Specified Condition
      U2-5 (RCO) - A34-11 (E) Always

      Below 1 V → 4.5 to 5.5 V

      (Pulse generation)
      U2-17 (RDAM) - A34-11 (E) Always 11 to 14 V

    NG

    REPLACE DOOR CONTROL RECEIVER Click here

    OK

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


    1. Disconnect the T2*1 or U2*2 certification ECU (smart key ECU assembly) connector.


      • *1: for LHD

      • *2: for RHD

    2. Disconnect the T32*1 or T33*2 door control receiver connector.


      • *1: for 12 Pin Type

      • *2: except 12 Pin Type

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

      Standard Resistance
      for 12 Pin Type (for LHD)
      Tester Connection Condition Specified Condition
      T2-5 (RCO) - T32-10 (+5) Always Below 1 Ω
      T2-17 (RDAM) - T32-9 (DATA) Always Below 1 Ω
      T2-5 (RCO) or T32-10 (+5) - Body ground Always 10 kΩ or higher
      T2-17 (RDAM) or T32-9 (DATA) - Body ground Always 10 kΩ or higher
      for 12 Pin Type (for RHD)
      Tester Connection Condition Specified Condition
      U2-5 (RCO) - T32-10 (+5) Always Below 1 Ω
      U2-17 (RDAM) - T32-9 (DATA) Always Below 1 Ω
      U2-5 (RCO) or T32-10 (+5) - Body ground Always 10 kΩ or higher
      U2-17 (RDAM) or T32-9 (DATA) - Body ground Always 10 kΩ or higher
      except 12 Pin Type (for LHD)
      Tester Connection Condition Specified Condition
      T2-5 (RCO) - T33-2 (+5) Always Below 1 Ω
      T2-17 (RDAM) - T33-3 (DATA) Always Below 1 Ω
      T2-5 (RCO) or T33-2 (+5) - Body ground Always 10 kΩ or higher
      T2-17 (RDAM) or T33-3 (DATA) - Body ground Always 10 kΩ or higher
      except 12 Pin Type (for RHD)
      Tester Connection Condition Specified Condition
      U2-5 (RCO) - T33-2 (+5) Always Below 1 Ω
      U2-17 (RDAM) - T33-3 (DATA) Always Below 1 Ω
      U2-5 (RCO) or T33-2 (+5) - Body ground Always 10 kΩ or higher
      U2-17 (RDAM) or T33-3 (DATA) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (DOOR CONTROL RECEIVER - AMPLIFIER ANTENNA ASSEMBLY)


    1. Disconnect the T51*1 or T33*2 control receiver connector.


      • *1: for 12 Pin Type

      • *2: except 12 Pin Type

    2. Disconnect the T52 amplifier antenna assembly connector.

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

      Standard Resistance
      for 12 Pin Type
      Tester Connection Condition Specified Condition
      T51-1 (ANT) - T52-1 (ANT) Always Below 1 Ω
      T51-1 (ANT) or T52-1 (ANT) - Body ground Always 10 kΩ or higher
      except 12 Pin Type
      Tester Connection Condition Specified Condition
      T33-7 (ANT) - T52-1 (ANT) Always Below 1 Ω
      T33-7 (ANT) or T52-1 (ANT) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. REPLACE AMPLIFIER ANTENNA ASSEMBLY


    1. Temporarily replacing the amplifier antenna assembly with a new or normally functioning one Click here.


    NEXT

  7. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  8. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B1242 is not output.

    NG

    REPLACE DOOR CONTROL RECEIVER Click here

    OK

    END (AMPLIFIER ANTENNA ASSEMBLY IS DEFECTIVE)

  9. REPLACE DOOR CONTROL RECEIVER


    1. Temporarily replacing the door control receiver with a new or normally functioning one Click here.


    NEXT

  10. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  11. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B1242 is not output.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    END (DOOR CONTROL RECEIVER IS DEFECTIVE)