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DTC B1220 (56)

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DTC B1220 or DTC indicator 56  : 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  

DTCs (AC)

  1. Problem verification

    -1. Clear the DTCs with the HDS.

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

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

    -4. Check for DTCs.

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

    Is DTC B1220 or 56 indicated?

    YES 

    The failure is duplicated. 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 (S5V line, others)

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

    -2. Disconnect the following connector.

    Recirculation control motor 5P 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 5P connector: disconnected
    Test point 1 Recirculation control motor 5P connector (female terminals) No. 5:
    Test point 2 Body ground
    GHH395997Courtesy of HONDA, U.S.A., INC.

    Is there about 5 V?

    YES 

    The S5V wire is OK. Go to step 3.

    NO 

    Go to step 6.

  3. Determine possible failure area (recirculation control motor, others)

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

    Test condition Vehicle ON mode
    Recirculation control motor 5P connector: disconnected
    Test point 1 Recirculation control motor 5P connector (female terminals) No. 4:
    Test point 2 Body ground
    GHH395999Courtesy of HONDA, U.S.A., INC.

    Is there about 5 V?

    YES 

    Replace the recirculation control motor .

    NO 

    Go to step 4.

  4. Shorted wire check (RFD-P line)

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

    -2. Disconnect the following connector.

    Climate control unit connector B (24P)

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

    Test condition Vehicle OFF (LOCK) mode
    Climate control unit connector B (24P): disconnected
    Recirculation control motor 5P connector: disconnected
    Test point 1 Climate control unit connector B (24P) No. 4
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the RFD-P wire.

    NO 

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

  5. Shorted wire check (RFD-P line to SENS-COM line)

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

    Test condition Vehicle OFF (LOCK) mode
    Climate control unit connector B (24P): disconnected
    Recirculation control motor 5P connector: disconnected
    Test point 1 Recirculation control motor 5P connector (female terminals) No. 3:
    Test point 2 Recirculation control motor 5P connector (female terminals) No. 4:
    GHH396002Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the RFD-P wire to SENS-COM wire.

    NO 

    Replace the climate control unit .

  6. Open wire check (S5V line)

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

    Test condition Vehicle ON mode
    Recirculation control motor 5P connector: disconnected
    Test point 1 Climate control unit connector B (24P) No. 1
    Test point 2 Body ground

    Is there about 5 V?

    YES 

    Repair an open in the S5V wire.

    NO 

    The S5V wire is not open. Go to step 7.

  7. Shorted wire check (S5V line)

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

    -2. Disconnect the following connector.

    Climate control unit connector B (24P)

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

    Test condition Vehicle OFF (LOCK) mode
    Climate control unit connector B (24P): disconnected
    Recirculation control motor 5P connector: disconnected
    Test point 1 Climate control unit connector B (24P) No. 1
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the S5V wire.

    NO 

    Replace the climate control unit .