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DTC B1245 (J and WINDSHIELD DEFROST) (Climate Control Unit)

DTC B1245 or DTC indicator J and WINDSHIELD DEFROST  : A short in the rear air mix 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
B1245 A short in the rear air mix control motor circuit  

DTCs (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 climate control unit .

    -4. Wait for at least 8 seconds.

    -5. Check for DTCs.

    DTC Description DTC
    B1245 A short in the rear air mix control motor circuit  

    Is DTC B1245 or J and WINDSHIELD DEFROST indicated?

    YES 

    Go to step 2.

    NO 

    Intermittent failure. Check for loose wires or poor connections on the rear air mix 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.

    Rear air mix 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
    Rear air mix control motor 7P connector: disconnected
    Test point 1 Rear air mix control motor 7P connector (female terminals) No. 3:
    Test point 2 Body ground
    GHH457023Courtesy 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. Rear air mix control motor check (AMDP RR line)

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

    Test condition Vehicle ON mode
    Rear air mix control motor 7P connector: disconnected
    Test point 1 Rear air mix control motor 7P connector (female terminals) No. 2:
    Test point 2 Body ground
    GHH457025Courtesy of HONDA, U.S.A., INC.

    Is there about 5 V?

    YES 

    The AMDP RR wire is OK. Replace the rear air mix control motor .

    NO 

    Go to step 4.

  4. Shorted wire check (AMDP RR line)

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

    -2. Disconnect the following connector.

    Climate control unit connector C (12P)

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

    Test condition Vehicle OFF (LOCK) mode
    Climate control unit connector C (12P): disconnected
    Rear air mix control motor 7P connector: disconnected
    Test point 1 Climate control unit connector C (12P) No. 6
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to body ground in the wire between the climate control unit and the rear air mix control motor.

    NO 

    The AMDP RR wire is not shorted. Go to step 5.

  5. Shorted wire check (AMDP RR line to SENSOR(COM) line)

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

    Test condition Vehicle OFF (LOCK) mode
    Climate control unit connector C (12P): disconnected
    Rear air mix control motor 7P connector: disconnected
    Test point 1 Rear air mix control motor 7P connector (female terminals) No. 1:
    Test point 2 Rear air mix control motor 7P connector (female terminals) No. 2:
    GHH457028Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the wires between the climate control unit and the rear air mix control motor.

    NO 

    The AMDP RR wire to SENSOR(COM) wire are OK. Replace the climate control unit .

  6. Open wire check (SENSOR 5V line)

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

    Test condition Vehicle ON mode
    Rear air mix control motor 7P connector: disconnected
    Test point 1 Climate 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 climate control unit and the rear air mix 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.

    Climate control unit connector A (32P)

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

    Test condition Vehicle OFF (LOCK) mode
    Climate control unit connector A (32P): disconnected
    Rear air mix control motor 7P connector: disconnected
    Test point 1 Climate 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 climate control unit and the rear air mix control motor.

    NO 

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