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DTC P2176

DTC P2176  : Throttle Actuator Control System Idle Position Not Learned

Do not insert your fingers into the installed throttle body when you turn the vehicle to the ON mode, or while the vehicle is in ON mode. If you do, you will seriously injure your fingers if the throttle valve is activated.
NOTE:
DTC Description Confirmed DTC Pending DTC
P2176 Throttle Actuator Control System Idle Position Not Learned    

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, and wait for 10 seconds.

    -4. Turn the vehicle to the ON mode.

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

    DTC Description Confirmed DTC Pending DTC
    P2176 Throttle Actuator Control System Idle Position Not Learned    

    DTC (PGM-FI)

    Is DTC P2176 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 throttle body and the PCM, then clean the throttle body . 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. Throttle body operation check

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

    -2. Remove the air intake tube .

    -3. Turn the vehicle to the ON mode.

    -4. Clear the DTC with the HDS.

    -5. Turn the vehicle to the OFF (LOCK) mode.

    -6. Turn the vehicle to the ON mode.

    -7. Visually check the throttle valve operation while doing the ETCS TEST in the Function Test Menu with the HDS.

    ETCS TEST

    Does the throttle valve move to its fully closed position?

    YES 

    Go to step 3.

    NO 

    Go to step 4.

  3. Throttle body condition check

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

    -2. Remove the throttle body .

    -3. Check for sludge or carbon on the throttle valve.

    Is there sludge or carbon on the throttle valve?

    YES 

    Clean the throttle body .

    NO 

    Replace the throttle body .

  4. Open wire check (MTR1 line, MTR2 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.

    PCM connector E (80P)
    Throttle body 6P connector

    -4. Connect terminals A and B with a jumper wire.

    Terminal A Throttle body 6P connector (female terminals) No. 1:
    Terminal B Throttle body 6P connector (female terminals) No. 2:
    GHH385431Courtesy of HONDA, U.S.A., INC.

    -5. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      PCM connector E (80P): disconnected
      Throttle body 6P connector: disconnected
      Throttle body 6P connector No. 1 and No. 2: jumped
    Test point 1 PCM connector E (80P) No. 27
    Test point 2 PCM connector E (80P) No. 28

    Is there continuity?

    1. YES 

      The MTR1 wire and the MTR2 wire are OK. Substitute a known-good throttle body , then recheck:

      NO 

      Repair an open in the MTR1 wire and/or the MTR2 wire between the PCM (E27, E28) and the throttle body.