GPEC

P2112-ELECTRONIC THROTTLE CONTROL - UNABLE TO OPEN

For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
Ignition on and battery voltage greater than 10 volts.

- Set Condition:
Just after key on, the throttle is opened and closed to test the system. If the PCM detects that the TP Sensor does not move from Limp Home Position, this DTC will set. One trip fault. The DTC will set within 5 seconds. ETC light is flashing.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

Diagnostic Test

1. ACTIVE DTC

NOTE: Diagnose any TP Sensor or 5 Volt Supply DTCs before continuing.

Turn the ignition on.
Start the engine and allow it to reach normal operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking For An Intermittent DTC

2. THROTTLE PLATE INSPECTION
Turn the ignition off.
Remove the air cleaner assembly.
Check for any signs of a foreign material (ice or dirt) on the throttle plate or in the throttle bore that can cause the throttle plate to stick or not open.
Attempt to manually open the throttle plate. Use an appropriate tool that will not damage or mar the throttle body.
Were any problems found?

Yes

- Repair as necessary or replace the Throttle Body Assembly. Disconnect the battery when replacing the Throttle Body Assembly. After installation is complete, use a scan tool and select the ETC Relearn function.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 3

3. TP SENSOR NO.1 AND TP SENSOR No. 2 BOTH EQUAL 2.5 VOLTS
With a scan tool, perform the Throttle Follower test and monitor both TP Sensor voltages.
Are both TP Sensor readings stuck at 2.5 volts?

Yes

- Check the TP Sensor Signal circuits for excessive resistance, being shorted together, or being shorted to the Sensor Ground circuit.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 4

4. (K124) ETC MOTOR (+) CIRCUIT SHORTED TO VOLTAGE

Turn the ignition off.
Disconnect the Throttle Body harness connector.
Disconnect the PCM harness connectors.
Turn the ignition on.
Measure the voltage of the (K124) ETC Motor (+) circuit.
Is there any voltage present?

Yes

- Repair the (K124) ETC Motor (+) circuit for a short to voltage.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 5

5. (K126) ETC MOTOR (-) CIRCUIT SHORTED TO VOLTAGE

Measure the voltage of the (K126) ETC Motor (-) circuit.
Is there any voltage present?

Yes

- Repair the (K126) ETC Motor (-) circuit for a short to voltage.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 6

6. (K124) ETC MOTOR (+) CIRCUIT SHORTED TO THE (K126) ETC MOTOR (-) CIRCUIT

Turn the ignition off.
Measure the resistance between the (K124) ETC Motor (+) circuit and the (K126) ETC Motor (-) circuit.
Is the resistance below 100 ohms?

Yes

- Repair the short to between the (K124) ETC Motor (+) circuit and the (K126) ETC Motor (-) circuit.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 7

7. (K124) ETC MOTOR (+) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K124) ETC Motor (+) circuit.
Is the resistance below 100 ohms?

Yes

- Repair the short to ground in the (K124) ETC Motor (+) circuit.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 8

8. (K126) ETC MOTOR (-) CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K126) ETC Motor (-) circuit.
Is the resistance below 100 ohms?

Yes

- Repair the short to ground in the (K126) ETC Motor (-) circuit.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 9

9. (K126) ETC MOTOR (-) CIRCUIT OPEN OR HIGH RESISTANCE

NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.

Measure the resistance of the (K124) ETC Motor (+) circuit.
Is the resistance below 5.0 ohms?

Yes

- Go to 11

No

- Repair the (K124) ETC Motor (+) circuit for an open circuit or high resistance.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

11. POWERTRAIN CONTROL MODULE (PCM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Throttle Body and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Replace and program the Powertrain Control Module.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.