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DTC P2603

DTC P2603  : Electric Engine Coolant Pump Circuit High Voltage

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P2603 Electric Engine Coolant Pump Circuit High Voltage    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Clear the DTC with the HDS.

    -3. Turn the vehicle to the OFF (LOCK) mode.

    -4. Enter the maintenance mode, then start the engine .

    -5. Select the Electric Water Pump TEST in the Function Test Menu with the HDS.

    Electric Water Pump TEST

    -6. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC
    P2603 Electric Engine Coolant Pump Circuit High Voltage    

    DTC (PGM-FI)

    Is DTC P2603 indicated?

    YES 

    The failure is duplicated. Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the electric engine coolant pump and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

  2. Open wire check (EWPC line)

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

    -2. Jump the SCS line with the HDS, and wait more than 1 minute.

    -3. Disconnect the following connectors.

    Electric engine coolant pump 5P connector
    PCM connector E (80P)

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

    Test condition Vehicle OFF (LOCK) mode
      Electric engine coolant pump 5P connector: disconnected
      PCM connector E (80P): disconnected
    Test point 1 Electric engine coolant pump 5P connector (female terminals) No. 4:
    Test point 2 PCM connector E (80P) No. 29
    GHH385566Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Go to step 3.

    NO 

    Repair an open in the EWPC wire between the PCM (E29) and the electric engine coolant pump.

  3. Electric engine coolant pump check

    -1. Substitute a known-good electric engine coolant pump .

    -2. Reconnect all connectors.

    -3. Exit the SCS mode with the HDS.

    -4. Turn the vehicle to the ON mode.

    -5. Clear the DTC with the HDS.

    -6. Turn the vehicle to the OFF (LOCK) mode.

    -7. Enter the maintenance mode, then start the engine .

    -8. Select the Electric Water Pump TEST in the Function Test Menu with the HDS.

    Electric Water Pump TEST

    -9. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC
    P2603 Electric Engine Coolant Pump Circuit High Voltage    

    DTC (PGM-FI)

    Is DTC P2603 indicated?

    YES 

    Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC P2603 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Replace the original electric engine coolant pump .