DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P2176

DTC P2176 : Throttle Actuator Control System Idle Position Not Learned

CAUTION:
Do not insert your fingers into the installed throttle body when you turn the ignition switch to ON (II), or while the ignition switch is in ON (II). If you do, you will seriously injure your fingers if the throttle valve is activated.

NOTE:
* Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How To Troubleshoot The Fuel And Emissions Systems.
* If DTC P2135 is stored at the same time as DTC P2176, troubleshoot DTC P2135 first, then recheck for DTC P2176.

1. Problem verification:

Problem verification
-1. Turn the ignition switch to ON (II).

-2. Clear the DTC with the HDS.

-3. Turn the ignition switch to LOCK (0).

-4. Turn the ignition switch to ON (II), and wait 10 seconds.

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

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 ECM, then clean the throttle body.

2. Throttle body operation check:

Throttle body operation check
-1. Turn the ignition switch to LOCK (0).

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

-3. Turn the ignition switch to ON (II).

-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.

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:

Throttle body condition check
-1. Turn the ignition switch to LOCK (0).

-2. Remove the throttle body Removal and Replacement.

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

Is there sludge or carbon on the throttle valve?
-YES- Clean the throttle body Throttle Body Cleaning, then do the repair verification.
-NO- Replace the throttle body Removal and Replacement, then do the repair verification.

4. Open wire check (MTR1 line, MTR2 line):

Open wire check (MTR1 line, MTR2 line)
-1. Turn the ignition switch to LOCK (0).

-2. Jump the SCS line with the HDS.

-3. Disconnect the following connectors.





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









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









Is there continuity?
-YES- The MTR1 and MTR2 wires are OK. Update the ECM Service and Repair if it does not have the latest software, or substitute a known-good ECM Service and Repair, then do the repair verification.
-NO- Repair an open in the MTR1 wire and/or the MTR2 wire between the ECM (C3, C4) and the throttle body, then do the repair verification.

Repair verification:

-1. Turn the ignition switch to LOCK (0).

-2. Reconnect all connectors.

-3. Turn the ignition switch to ON (II).

-4. Reset the ECM with the HDS How To Troubleshoot The Fuel And Emissions Systems.

-5. Do the ECM idle learn procedure ECM/PCM Idle Learn Procedure.

-6. Turn the ignition switch to LOCK (0).

-7. Turn the ignition switch to ON (II), and wait 10 seconds.

-8. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P2176 indicated?
-YES- Check for poor connections or loose terminals at the throttle body and the ECM, then clean the throttle body Throttle Body Cleaning, and go to step 1. If the ECM was updated, substitute a known-good ECM Service and Repair, then recheck. If the ECM was substituted, go to step 1.
-NO- Troubleshooting is complete. If the ECM was substituted, replace the original ECM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.