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DTC B1220 (5)

DTC B1220 or DTC indicator 5  : A Short in the Recirculation Control Motor Circuit

NOTE:

If other short circuit DTCs are indicated at the same time, there may be an open or short to body ground in the power (5 V) circuit.

DTC Description DTC
B1220 A Short in the recirculation control motor circuit  

DTC (AC)

  1. Problem verification

    - 1. Clear the DTC 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
    B1220 A short in the recirculation control motor circuit  

    Is DTC B1220 or 5 indicated?

    YES 

    Go to step 2.

    NO 

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

  2. Determine possible failure area (SENSOR 5V line, others)

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

    - 2. Disconnect the following connector.

    Recirculation control motor 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
    Recirculation control motor 7P connector: disconnected
    Test point 1 Recirculation control motor 7P connector No. 1
    Test point 2 Body ground
    GHH310010Courtesy of HONDA, U.S.A., INC.

    Is there about 5 V?

    YES 

    The SENSOR 5V wire is OK. Go to step 3.

    NO 

    Go to step 6.

  3. Recirculation control motor check (FRS REC-P line)

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

    Test condition Vehicle ON mode
    Recirculation control motor 7P connector: disconnected
    Test point 1 Recirculation control motor 7P connector No. 2
    Test point 2 Body ground
    GHH310011Courtesy of HONDA, U.S.A., INC.

    Is there about 5 V?

    YES 

    The FRS REC-P wire is OK. Replace the recirculation control motor .

    NO 

    Go to step 4.

  4. Shorted wire check (FRS REC-P line)

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

    - 2. Disconnect the following connector.

    HVAC control unit connector C (12P)

    - 3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
    HVAC control unit connector C (12P): disconnected
    Recirculation control motor 7P connector: disconnected
    Test point 1 HVAC control unit connector C (12P) No. 5
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to body ground in the wire between the HVAC control unit and the recirculation control motor.

    NO 

    The FRS REC-P wire is not shorted. Go to step 5.

  5. Shorted wire check (FRS REC-P line to SENSOR(COM) line)

    - 1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
    HVAC control unit connector C (12P): disconnected
    Recirculation control motor 7P connector: disconnected
    Test point 1 Recirculation control motor 7P connector No. 2
    Test point 2 Recirculation control motor 7P connector No. 3
    GHH310012Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the wires between the HVAC control unit and the recirculation control motor.

    NO 

    The FRS REC-P wire to SENSOR(COM) wire are OK. Replace the HVAC control unit .

  6. Open wire check (SENSOR 5V line)

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

    Test condition Vehicle ON mode
    Recirculation control motor 7P connector: disconnected
    Test point 1 HVAC control unit connector A (32P) No. 5
    Test point 2 Body ground

    Is there about 5 V?

    YES 

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

    NO 

    The SENSOR 5V wire is not open. Go to step 7.

  7. Shorted wire check (SENSOR 5V line)

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

    - 2. Disconnect the following connector.

    HVAC control unit connector A (32P)

    - 3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
    HVAC control unit connector A (32P): disconnected
    Recirculation control motor 7P connector: disconnected
    Test point 1 HVAC control unit connector A (32P) No. 5
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to body ground in the wire between the HVAC control unit and the recirculation control motor.

    NO 

    The SENSOR 5V wire is OK. Replace the HVAC control unit .