WIRELESS DOOR LOCK CONTROL SYSTEM, Diagnostic DTC:B1242

DTC Code DTC Name
B1242 Wireless Door Lock Tuner Circuit Malfunction

DESCRIPTION

The electrical key and tire pressure monitoring system receiver assembly 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 electrical key and tire pressure monitoring system receiver assembly. The electrical key and tire pressure monitoring system receiver assembly 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 to ground in RDAM terminal circuit between the certification ECU (smart key ECU assembly) and electrical key and tire pressure monitoring system receiver assembly.

  • Short to ground in RDAM terminal circuit when voltage (5 V) is not being output from terminal RCO

  • Wire harness or connector

  • Electrical key and tire pressure monitoring system receiver assembly

  • Certification ECU (smart key ECU assembly)

WIRING DIAGRAM

A003K28E35

CAUTION / NOTICE / HINT

Note


  • When replacing or inspecting the electrical key and tire pressure monitoring system receiver assembly and wire harness, do not change the position or length of the wire harness. If the wire harness is too close to the electrical key and tire pressure monitoring system receiver assembly, the performance of the entry function and wireless function may be affected.

  • This DTC is not stored within 10 seconds of the power 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

  • Before replacing the certification ECU (smart key ECU assembly), refer to Service Bulletin.

  • When replacing the electrical key and tire pressure monitoring system receiver assembly, 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 electrical key and tire pressure monitoring system receiver assembly if the electrical key and tire pressure monitoring system receiver assembly has been replaced.

    Click here

PROCEDURE


  1. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. Disconnect the N14 electrical key and tire pressure monitoring system receiver assembly connector.

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

      A003N3LC05
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      		 - -
      Standard Voltage
      Tester Connection Condition Specified Condition
      N54-19 (RDAM) - I1-18 (E) Always 11 to 14 V
      N54-18 (RCO) - I1-18 (E) Always Below 1 V → 4.5 to 5.5 V pulse generation at regular intervals
      Standard Resistance
      Tester Connection Condition Specified Condition
      I1-18 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ELECTRICAL KEY AND TIRE PRESSURE MONITORING SYSTEM RECEIVER ASSEMBLY Click here

    NG

  2. CHECK HARNESS AND CONNECTOR (ELECTRICAL KEY AND TIRE PRESSURE MONITORING SYSTEM RECEIVER ASSEMBLY - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))


    1. Disconnect the I1 and N54 certification ECU (smart key ECU assembly) connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      N54-19 (RDAM) - N14-9 (DATA) Always Below 1 Ω
      N54-18 (RCO) - N14-10 (+5) Always Below 1 Ω
      N14-12-(GND) - Body ground Always Below 1 Ω
      N14-9 (DATA) or N54-19 (RDAM) - Body ground Always 10 kΩ or higher
      N14-10 (+5) or N54-18 (RCO) - 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