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DTC P1448: Intelligent Power Unit (IPU) Module Fan Problem (63) (2014-15)

DTC Description Confirmed DTC Pending DTC Freeze Frame
P1448 Intelligent Power Unit (IPU) Module Fan Problem      

DTCs (HEV)

  1. Problem verification

    - 1. Turn the vehicle to the ON mode.

    - 2. Clear the DTC with the HDS.

    - 3. Do the BATTERY FAN TEST in the INSPECTION MENU with the HDS.

    BATTERY FAN TEST

    Is the result OK?

    YES 

    Intermittent failure, the system is OK at this time. Check for poor connections, loose terminals, or damaged insulation at high voltage battery module fan and the battery condition monitor module.

    NO 

    Go to step 2.

  2. Open wire check (IGA2-2 line)

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

    - 2. Disconnect the following connector.

    High voltage battery module fan 4P connector - Refer to: High Voltage Battery Module Fan Removal and Installation (2014-15)

    - 3. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
      High voltage battery module fan 4P connector: disconnected
    Test circuit IGA2-2
    Test point 1 High voltage battery module fan 4P connector No. 4 (LT GRN)
    Test point 2 Body ground
    GHH255826Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Go to step 7.

    NO 

    Go to step 3.

  3. OBD status check

    - 1. Monitor the OBD STATUS for DTC P0AE1 in the DTCs MENU with the HDS.

    DTC Description OBD STATUS
    P0AE1 High Voltage Bypass Contactor Malfunction  

    Does the HDS indicate FAILED?

    YES 

    Multiple DTC will be detected by the power supply line failure (IGB line). Check the IGHLDB relay circuit.

    NO 

    Go to step 4

  4. Relay check

    - 1. Remove the rear bulkhead gusset.

    - 2. Remove battery fan relay (A).

    GHH255827Courtesy of HONDA, U.S.A., INC.

    - 3. Test battery fan relay.

    Is the relay OK?

    YES 

    Go to step 5.

    NO 

    Replace battery fan relay.

  5. Open wire check (+B IGA2 line)

    - 1. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
      Battery fan relay: disconnected
    Test circuit +B IGA2
    Test point 1 IPU relay holder No. 6 (PNK)
    Test point 2 Body ground
    GHH255828Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Go to step 6.

    NO 

    Repair an open in the +B IGA2 wire between battery fan relay and the under-dash sub fuse box No. C2 (10 A) fuse.

  6. Open wire check (IGA2/IGA2-2 line)

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

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

    Test condition Vehicle OFF (LOCK) mode
      Battery fan relay: disconnected
      High voltage battery module fan 4P connector: disconnected
    Test circuit IGA2/IGA2-2
    Test point 1 IPU relay holder No. 5 (RED)
    Test point 2 High voltage battery module fan 4P connector No. 4 (LT GRN)
    GHH255829Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Check for poor connections, loose terminals, or damaged insulation at IPU relay holder, and recheck.

    NO 

    Repair an open in the IGA2/IGA2-2 wire between battery fan relay and the high voltage battery module fan.

  7. Open wire check (PG line)

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

    Test condition Vehicle ON mode
      High voltage battery module fan 4P connector: disconnected
    Test circuit IGA2-2, PG
    Test point 1 High voltage battery module fan 4P connector No. 4 (LT GRN)
    Test point 2 High voltage battery module fan 4P connector No. 1 (BLK)
    GHH255830Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Go to step 8.

    NO 

    Repair an open in the PG wire between the high voltage battery module fan and G652.

  8. Determine possible failure area (NFAN BATT2 line)

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

    Test condition Vehicle ON mode
      High voltage battery module fan 4P connector: disconnected
    Test circuit NFAN BATT2
    Test point 1 High voltage battery module fan 4P connector No. 3 (BLU)
    Test point 2 Body ground
    GHH255831Courtesy of HONDA, U.S.A., INC.

    Is there about 5.0 V?

    YES 

    Go to step 11.

    NO 

    Go to step 9.

  9. Shorted wire check (NFAN BATT2 line)

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

    - 2. Do the 12 volt battery terminal disconnection procedure.

    - 3. Disconnect the following connector.

    Battery condition monitor module connector A (36P) - Refer to: Battery Condition Monitor Module Removal and Installation (2014-15)

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

    Test condition Vehicle OFF (LOCK) mode
      Battery condition monitor module connector A (36P): disconnected
      High voltage battery module fan 4P connector: disconnected
    Test circuit NFAN BATT2
    Test point 1 High voltage battery module fan 4P connector No. 3 (BLU)
    Test point 2 Body ground
    GHH255832Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the NFAN BATT2 wire between the high voltage battery module fan and the battery condition monitor module (A23).

    NO 

    Go to step 10.

  10. Open wire check (NFAN/NFAN BATT2 line)

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

    Test condition Vehicle OFF (LOCK) mode
      Battery condition monitor module connector A (36P): disconnected
      High voltage battery module fan 4P connector: disconnected
    Test circuit NFAN/NFAN BATT2
    Test point 2 Battery condition monitor module connector A (36P) No. 5 (YEL)
    Test point 1 High voltage battery module fan 4P connector No. 3 (GRN)
    GHH255833Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Update the battery condition monitor module if it does not have the latest software, or substitute a known-good battery condition monitor module - Refer to: Battery Condition Monitor Module Removal and Installation (2014-15) .

    NO 

    Repair an open in the NFAN/NFAN BATT2 wire between the high voltage battery module fan and the battery condition monitor module (A5).

  11. Open wire check (FANCTL line)

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

    - 2. Do the 12 volt battery terminal disconnection procedure.

    - 3. Reconnect the high voltage battery module fan 4P connector.

    - 4. Do the 12 volt battery terminal reconnection procedure.

    - 5. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
      Battery condition monitor module connector A (36P): connected
      High voltage battery module fan 4P connector: connected
    Test circuit FANCTL
    Test point 1 Battery condition monitor module connector A (36P) No. 21 (PNK)
    Test point 2 Body ground
    GHH255834Courtesy of HONDA, U.S.A., INC.

    Is there about 5.0 V?

    YES 

    Update the battery condition monitor module if it does not have the latest software, or substitute a known-good battery condition monitor module - Refer to: Battery Condition Monitor Module Removal and Installation (2014-15) .

    NO 

    Go to step 12.

  12. Shorted wire check (FANCTL line)

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

    - 2. Do the 12 volt battery terminal disconnection procedure.

    - 3. Disconnect the following connector.

    Battery condition monitor module connector A (36P) - Refer to: Battery Condition Monitor Module Removal and Installation (2014-15)
    High voltage battery module fan 4P connector - Refer to: High Voltage Battery Module Fan Removal and Installation (2014-15)

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

    Test condition Vehicle OFF (LOCK) mode
      Battery condition monitor module connector A (36P): disconnected
      High voltage battery module fan 4P connector: connected
    Test circuit FANCTL
    Test point 1 Battery condition monitor module connector A (36P) No. 21 (PNK)
    Test point 2 Body ground
    GHH255835Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the FANCTL wire between high voltage battery module fan and the battery condition monitor module (A21).

    NO 

    Go to step 13.

  13. Open wire check (FANCTL/FANCTL BATT2 line)

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

    Test condition Vehicle OFF (LOCK) mode
      Battery condition monitor module connector A (36P): disconnected
      High voltage battery module fan 4P connector: connected
    Test circuit FANCTL/FANCTL BATT2
    Test point 1 Battery condition monitor module connector A (36P) No. 21 (PNK)
    Test point 2 High voltage battery module fan 4P connector No. 2 (GRN)
    GHH255836Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Replace the high voltage battery module fan - Refer to: High Voltage Battery Module Fan Removal and Installation (2014-15) .

    NO 

    Repair an open in the FANCTL/FANCTL BATT2 wire between high voltage battery module fan and the battery condition monitor module (A21).

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