HEATED STEERING WHEEL SYSTEM, Diagnostic DTC:B14B7

DTC Code DTC Name
B14B7 Lost Communication with Steering Heater ECU

DESCRIPTION

The steering wheel heater control assembly communicates with the air conditioning amplifier assembly via LIN communication.

B14B7 is output when a communication malfunction is detected with the air conditioner amplifier assembly and steering wheel heater control assembly (steering wheel assembly).

DTC No. Detection Item DTC Detection Condition Trouble Area
B14B7 Lost Communication with Steering Heater ECU

  • Diagnosis condition: Power switch on (IG)

  • Malfunction status: Lost communication with air conditioning amplifier assembly and steering wheel heater control assembly

  • Detection time: Continuously for 10 seconds or more

  • Steering wheel heater control assembly

  • Air conditioning amplifier assembly

  • Integration control and panel assembly

  • Spiral with sensor cable sub-assembly

  • Harness or connector

WIRING DIAGRAM

B000O7EE04

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses for circuits related to this system before performing the following procedure.

  • The vehicle is equipped with a Supplemental Restraint System (SRS) which includes components such as airbags. Before servicing (including removal or installation of parts), be sure to read the precaution for Supplemental Restraint System.

    Click here

PROCEDURE


  1. CHECK FOR DTCs


    1. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Result
      Result Proceed to
      Only DTC B14B7 is output A
      DTC B14B2 and B14B7 are output B

    B

    CHECK HARNESS OR CONNECTOR (SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY AND INTEGRATION CONTROL & PANEL ASSEMBLY) Click here

    A

  2. CHECK HARNESS OR CONNECTOR (STEERING WHEEL HEATER CONTROL ASSEMBLY POWER SOURCE CIRCUIT)


    1. B000TNDC02
      *a

      Front view of wire harness connector

      (to Spiral with Sensor Cable Sub-assembly)

      Disconnect the P20 spiral with sensor cable sub-assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      P20-4 (BHT) - Body ground Power switch on (IG) 11 to 14 V
      P20-4 (BHT) - Body ground Power switch off Below 1 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      P20-2 (EHT) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STEERING WHEEL HEATER CONTROL ASSEMBLY POWER SOURCE CIRCUIT)

    OK

  3. INSPECT SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY


    1. Remove the spiral with sensor cable sub-assembly.

      Click here

    2. Inspect the spiral with sensor cable sub-assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY Click here

    OK

  4. CHECK HARNESS OR CONNECTOR (SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY AND INTEGRATION CONTROL AND PANEL ASSEMBLY)


    1. Disconnect the P20 spiral with sensor cable sub-assembly connector.

    2. Disconnect the P58 air conditioning amplifier assembly connector.

    3. Disconnect the P73 integration control and panel assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      P20-3 (LIN) - P58-14 (LIN1) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE STEERING WHEEL HEATER CONTROL ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY AND INTEGRATION CONTROL AND PANEL ASSEMBLY)

  5. CHECK HARNESS OR CONNECTOR (SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY AND INTEGRATION CONTROL & PANEL ASSEMBLY)


    1. Disconnect the P20 spiral with sensor cable sub-assembly connector.

    2. Disconnect the P58 air conditioning amplifier assembly connector.

    3. Disconnect the P73 integration control and panel assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      P20-3 (LIN) - P58-14 (LIN1) Always Below 1 Ω
      P20-3 (LIN), P58-14 (LIN1) or P73-6 (LIN1) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY AND INTEGRATION CONTROL AND PANEL ASSEMBLY)

    OK

  6. CHECK FOR DTCs


    1. Clear the DTCs.

      Click here


      Body Electrical > Air Conditioner > Clear DTCs

    2. Disconnect the P73 integration control and panel assembly connector.

    3. Make sure that the DTC detection conditions are met.

      Tech Tips

      If the detection conditions are not met, the system cannot detect the malfunction.

    4. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Result
      Result Proceed to
      Only DTC B14B2 is output A
      DTC B14B2 and B14B7 are output B

    A

    REPLACE INTEGRATION CONTROL AND PANEL ASSEMBLY Click here

    B

  7. CHECK FOR DTCs


    1. Clear the DTCs.

      Click here


      Body Electrical > Air Conditioner > Clear DTCs

    2. Disconnect the z15 spiral with sensor cable sub-assembly connector.

    3. Make sure that the DTC detection conditions are met.

      Tech Tips

      If the detection conditions are not met, the system cannot detect the malfunction.

    4. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Result
      Result Proceed to
      Only DTC B14B7 is output A
      DTC B14B2 and B14B7 are output B

    A

    REPLACE STEERING WHEEL HEATER CONTROL ASSEMBLY Click here

    B

  8. CHECK FOR DTCs


    1. Clear the DTCs.

      Click here


      Body Electrical > Air Conditioner > Clear DTCs

    2. Disconnect the P20 spiral with sensor cable sub-assembly connector.

    3. Make sure that the DTC detection conditions are met.

      Tech Tips

      If the detection conditions are not met, the system cannot detect the malfunction.

    4. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Result
      Result Proceed to
      Only DTC B14B7 is output A
      DTC B14B2 and B14B7 are output B

    A

    REPLACE SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY Click here

    B

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here