LEMON Manuals: Even more car manuals for everyone
Home >> Honda >> 2021 >> Pilot Special Edition, AWD >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> HVAC System - DTC Diagnostics >> DTC Troubleshooting >> DTC B2972 (7)

DTC B2972 (7)

DTC B2972 or DTC indicator 7  : An Open in the Mode Control Motor B Circuit (Front)

DTC Description DTC
B2972 An open in the mode control motor B circuit (front)  

DTCs (AC)

  1. Problem verification

    - 1. Clear the DTCs with the HDS.

    - 2. Turn the vehicle to the OFF (LOCK) mode then the ON mode.

    - 3. Do the Self-Diagnostic Function with the HDS or the HVAC control unit.

    - 4. Wait for at least 8 seconds.

    - 5. Check for DTCs.

    DTC Description DTC
    B2972 An open in the mode control motor B circuit (front)  

    Is DTC B2972 or 7 indicated?

    YES 

    Go to step 2.

    NO 

    Intermittent failure. Check for loose wires or poor connections on the mode control motor B circuit.

  2. Determine possible failure area (MOD-P HD line, others)

    - 1. Turn the vehicle to the OFF (LOCK) mode.

    - 2. Disconnect the following connector.

    Mode control motor B 7P connector

    - 3. Turn the vehicle to the ON mode.

    - 4. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
    Mode control motor B 7P connector: disconnected
    Test point 1 Mode control motor B 7P connector No. 2
    Test point 2 Body ground
    GHH310135Courtesy of HONDA, U.S.A., INC.

    Is there about 5 V?

    YES 

    The MOD-P HD wire is OK. Go to step 3.

    NO 

    Go to step 4.

  3. Open wire check (SENSOR(COM) line)

    - 1. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
    Mode control motor B 7P connector: disconnected
    Test point 1 Mode control motor B 7P connector No. 2
    Test point 2 Mode control motor B 7P connector No. 3
    GHH310136Courtesy of HONDA, U.S.A., INC.

    Is there about 5 V?

    YES 

    Replace the mode control motor B .

    NO 

    Repair an open in the wire between the HVAC control unit and the mode control motor B.

  4. Open wire check (MOD-P HD line)

    - 1. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
    Mode control motor B 7P connector: disconnected
    Test point 1 HVAC control unit connector C (12P) No. 4
    Test point 2 Body ground

    Is there about 5 V?

    YES 

    Repair an open in the wire between the HVAC control unit and the mode control motor B.

    NO 

    Replace the HVAC control unit .