DTC P2176: Throttle Actuator Control System Idle Position Not Learned

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

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: 

• Before you troubleshoot, review the general troubleshooting information - Refer to: HOW TO TROUBLESHOOT THE FUEL AND EMISSIONS SYSTEMS or How to Troubleshoot the CVT System(CVT) .
• If DTC P2135 is stored at the same time as DTC P2176, troubleshoot DTC P2135 first, then recheck for DTC P2176.

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 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	Freeze Frame
   P2176 Throttle Actuator Control System Idle Position Not Learned

   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 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. Throttle body operation check:

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

   - 2. Disconnect the intake air duct from the throttle body .

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTC with the HDS.

   - 5. Visually check the throttle valve operation while doing the ETCS TEST in the INSPECTION 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.

   SCS Short

   - 3. Disconnect the following connectors.

   PCM connector C (51P)

   Throttle body 6P connector

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

   Terminal A	Throttle body 6P connector No. 1
   Terminal B	Throttle body 6P connector No. 2

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

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector C (51P): disconnected
   	Throttle body 6P connector: disconnected
   	Throttle body 6P connector No. 1 and No. 2: jumped
   Test point 1	PCM connector C (51P) No. 11
   Test point 2	PCM connector C (51P) No. 12

   Is there continuity?

   YES 

   The MTR1 and MTR2 wires are OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P2176 goes away and the PCM was updated, troubleshooting is complete. If DTC P2176 goes away and the PCM was substituted, replace the original PCM .

   NO 

   Repair an open in the MTR1 wire and/or the MTR2 wire between the PCM (C11, C12) and the throttle body.