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DTC P1728

DTC P1728  : Park Pawl Motor Voltage Low

NOTE: Before you troubleshoot, review the General Troubleshooting Information .
DTC Description Confirmed DTC Pending DTC Freeze Frame
P1728 Park Pawl Motor Voltage Low      

DTC (Gear)

  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. Turn the vehicle to the ON mode, and wait for at least 10 seconds.

    -5. Check for Pending or Confirmed DTCs with the HDS.

    DTC Description Confirmed DTC Pending DTC Freeze Frame
    P1728 Park Pawl Motor Voltage Low      

    Is DTC P1728 indicated?

    YES 

    The failure is duplicated. Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for poor connections and loose terminals between the park pawl actuator and the park pawl actuator driver unit. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

  2. Fuse check

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

    -2. Check the following fuse.

    Fuse No. G3

    Is the fuse OK?

    YES 

    The fuse is OK. Reinstall the fuse, then go to step 3.

    NO 

    Replace the No. G3 fuse, and recheck. If the fuse blows again, repair a short to ground in the No. G3 fuse circuit.

  3. Determine possible failure area (park pawl actuator relay circuit, others)

    -1. Disconnect the following connector.

    Park pawl actuator 10P connector

    -2. Turn the vehicle to the ON mode.

    -3. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
      Park pawl actuator 10P connector: disconnected
    Test point 1 Park pawl actuator 10P connector (female terminals) No. 2:
    Test point 2 Body ground
    GHH417720Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    Go to step 4.

    NO 

    Go to step 7.

  4. Shorted wire check (P-ACT MTR U/MAU line, P-ACT MTR V/MAV line, P-ACT MTR W/MAW line)

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

    -2. Disconnect the following connector.

    Park pawl actuator driver unit 26P connector

    -3. Check for continuity between the following test points and body ground individually.

    Test condition Vehicle OFF (LOCK) mode
      Park pawl actuator 10P connector: disconnected
      Park pawl actuator driver unit 26P connector: disconnected
    Connector Terminal
    Park pawl actuator 10P connector (female terminals): No. 1
    No. 6
    No. 7
    GHH417722Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short to ground in the P-ACT MTR U/MAU wire, the P-ACT MTR V/MAV wire, and/or the P-ACT MTR W/MAW wire between the park pawl actuator and the park pawl actuator driver unit.

    NO 

    The P-ACT MTR U/MAU wire, the P-ACT MTR V/MAV wire, and/or the P-ACT MTR W/MAW wire are not shorted to ground. Go to step 5.

  5. Open wire check (P-ACT MTR U/MAU line, P-ACT MTR V/MAV line, P-ACT MTR W/MAW line)

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

    Test condition Vehicle OFF (LOCK) mode
      Park pawl actuator 10P connector: disconnected
      Park pawl actuator driver unit 26P connector: disconnected
    Test point 1 Park pawl actuator 10P connector (female terminals) No. 1:
    Test point 2 Park pawl actuator driver unit 26P connector No. 6
    Test point 1 Park pawl actuator 10P connector (female terminals) No. 6:
    Test point 2 Park pawl actuator driver unit 26P connector No. 5
    Test point 1 Park pawl actuator 10P connector (female terminals) No. 7:
    Test point 2 Park pawl actuator driver unit 26P connector No. 4
    GHH417726Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The P-ACT MTR U/MAU wire, the P-ACT MTR V/MAV wire, and the P-ACT MTR W/MAW wire are OK. Go to step 6.

    NO 

    Repair an open in the P-ACT MTR U/MAU wire, the P-ACT MTR V/MAV wire, and/or the P-ACT MTR W/MAW wire between the park pawl actuator and the park pawl actuator driver unit.

  6. Park pawl actuator check

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

    Test condition Vehicle OFF (LOCK) mode
      Park pawl actuator 10P connector: disconnected
      Park pawl actuator driver unit 26P connector: disconnected
    Test point 1 Park pawl actuator 10P connector (male terminals) No. 2:
    Test point 2 Park pawl actuator 10P connector (male terminals) No. 1:
    Test point 1 Park pawl actuator 10P connector (male terminals) No. 2:
    Test point 2 Park pawl actuator 10P connector (male terminals) No. 6:
    Test point 1 Park pawl actuator 10P connector (male terminals) No. 2:
    Test point 2 Park pawl actuator 10P connector (male terminals) No. 7:
    GHH417733Courtesy of HONDA, U.S.A., INC.

    Is there 10 kΩ or more?

    YES 

    Replace the park pawl actuator .

    NO 

    The park pawl actuator is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good park pawl actuator driver unit , then recheck. If this DTC goes away and the park pawl actuator driver unit was substituted, replace the original park pawl actuator driver unit .

  7. Park pawl actuator relay check

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

    -2. Remove the park pawl actuator relay.

    -3. Test the park pawl actuator relay .

    Is the relay OK?

    YES 

    The park pawl actuator relay is OK. Keep the relay removed, and go to step 8.

    NO 

    Replace the park pawl actuator relay.

  8. Open wire check (power supply line on park pawl actuator relay)

    -1. Measure the voltage between the following test points and body ground individually.

    Test condition Vehicle OFF (LOCK) mode
      Park pawl actuator relay 4P socket: disconnected
      Park pawl actuator 10P connector: disconnected
    Connector Terminal
    Park pawl actuator relay 4P socket (female terminals): No. 1
    No. 3
    GHH417735Courtesy of HONDA, U.S.A., INC.

    Is there battery voltage?

    YES 

    The power supply wire is OK. Go to step 9.

    NO 

    Repair an open in the power supply wire in the under-hood fuse/relay box.

  9. Open wire check (P-ACT RLY OUT/BMA line)

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

    Test condition Vehicle OFF (LOCK) mode
      Park pawl actuator relay 4P socket: disconnected
      Park pawl actuator 10P connector: disconnected
    Test point 1 Park pawl actuator relay 4P socket (female terminals) No. 2:
    Test point 2 Park pawl actuator 10P connector (female terminals) No. 2:
    GHH417738Courtesy of HONDA, U.S.A., INC.
    GHH417739Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The P-ACT RLY OUT/BMA wire is OK. Go to step 10.

    NO 

    Repair an open in the P-ACT RLY OUT/BMA wire between the park pawl actuator relay and the park pawl actuator.

  10. Open wire check (P-ACT RLY CL- line)

    -1. Disconnect the following connector.

    Park pawl actuator driver unit 26P connector

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

    Test condition Vehicle OFF (LOCK) mode
      Park pawl actuator relay 4P socket: disconnected
      Park pawl actuator 10P connector: disconnected
      Park pawl actuator driver unit 26P connector: disconnected
    Test point 1 Park pawl actuator relay 4P socket (female terminals) No. 4:
    Test point 2 Park pawl actuator driver unit 26P connector No. 23
    GHH417741Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The P-ACT RLY CL- wire is not open. Go to step 11.

    NO 

    Repair an open in the P-ACT RLY CL- wire between the park pawl actuator relay and the park pawl actuator driver unit.

  11. Shorted wire check (P-ACT RLY CL- line to power)

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

    Test condition Vehicle OFF (LOCK) mode
      Park pawl actuator relay 4P socket: disconnected
      Park pawl actuator 10P connector: disconnected
      Park pawl actuator driver unit 26P connector: disconnected
    Test point 1 Park pawl actuator driver unit 26P connector No. 23
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Repair a short to power in the P-ACT RLY CL- wire between the park pawl actuator relay and the park pawl actuator driver unit.

    NO 

    The P-ACT RLY CL- wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good park pawl actuator driver unit , then recheck. If this DTC goes away and the park pawl actuator driver unit was substituted, replace the original park pawl actuator driver unit .

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