P2111
P2111-ELECTRONIC THROTTLE CONTROL - UNABLE TO CLOSE
Special Tools:
For a complete wiring diagram, refer to the Wiring Information.
Theory of operation
The Electronic Throttle Control (ETC) motor is controlled by the Powertrain Control Module (PCM). The DC motor located in the throttle body drives the throttle blade. In order to decrease idle speed, along with spark and fuel delivery changes the PCM commands the throttle closed reducing air flow into the engine and the idle speed decreases. In order to increase idle speed, the PCM commands the throttle plate open allowing more air to pass the throttle plate.
- 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 TP Sensor does not return to Limp Home Position at the end of this test, this DTC will set. One trip fault and the code will set within five seconds. ETC light is flashing.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
NOTE: Maximum engine speed could be reduced while this fault is active, it just depends where the throttle gets stuck.
1. Ignition on, engine not running.
NOTE: The PCM tests the ETC Motor by opening and closing the Throttle Plate before starting the engine. If during this test the Throttle plate does not return to the closed position this DTC sets.
2. With a scan tool, read the active DTCs.
NOTE: Diagnose any TP Sensor or 5-Volt Supply DTCs before continuing.
Is the DTC Active at this time?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.
2. THROTTLE PLATE STUCK OPEN
1. Turn the ignition off.
NOTE: The PCM tests the ETC Motor by opening and closing the Throttle Plate before starting the engine. If during this test the Throttle plate does not return to the closed position this DTC sets.
2. Remove the Air Cleaner Assembly from the Throttle Body. Air Cleaner Body - Removal.
3. Check for any signs of a foreign material causing the Throttle to remain open.
4. Using a scan tool, under System Tests, perform the ETC Throttle Follower Test.
5. Have an assistant watch the throttle plate to verify it moves during the test.
Does the Throttle Plate move?
Yes
- Go To 3
No
- Remove the debris if possible or replace the Throttle Body Assembly if signs of physical damage are present. Throttle Body - Removal. Disconnect the Battery when replacing the Throttle Body Assembly. After installation is complete, use a scan tool and perform the ETC RELEARN function.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
3. TP SENSOR NO.1 AND TP SENSOR NO.2 BOTH EQUAL 2.5 VOLTS
1. With a scan tool, perform the ETC Throttle Follower test while reading both TP Sensor voltage readings.
Are both TP Sensor readings stuck at 2.5 Volts?
Yes
- Check the TP Sensor Signal circuits for excessive resistance, being shorted to each other, or shorted to the Sensor Return circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 4
4. (K124) ETC POSITIVE CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Throttle Body harness connector.
3. Disconnect the C2 PCM harness connector.
CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the PCM Pinout Box to perform the diagnostics.
4. Ignition on, engine not running.
5. Measure the voltage on the (K124) ETC Positive circuit at the appropriate terminal of PCM Pinout Box.
Is there any voltage present?
Yes
- Repair the short to voltage on the (K124) ETC Positive circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 5
5. (K124) ETC POSITIVE CIRCUIT OPEN
1. Turn the ignition off.
2. Measure the resistance of the (K124) ETC Positive circuit from the Throttle Body harness connector to the appropriate terminal of PCM Pinout Box.
Is the resistance below 5.0 Ohms?
Yes
- Go To 6
No
- Repair the open in the (K124) ETC Positive circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
6. (K126) ETC NEGATIVE CIRCUIT OPEN
1. Measure the resistance of the (K126) ETC Negative circuit from the Throttle Body harness connector to the appropriate terminal of PCM Pinout Box.
Is the resistance below 5.0 Ohms?
Yes
- Go To 7
No
- Repair the open in the (K126) ETC Negative circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
7. (K124) ETC POSITIVE CIRCUIT SHORTED TO GROUND
1. Measure the resistance between a known good ground and the (K124) ETC Positive circuit at the appropriate terminal of PCM Pinout Box.
Is the resistance below 100 Ohms?
Yes
- Repair the short to ground in the (K124) ETC Positive circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 8
8. (K126) ETC NEGATIVE CIRCUIT SHORTED TO GROUND
1. Measure the resistance between a known good ground and the (K126) ETC Negative circuit at the appropriate terminal of PCM Pinout Box.
Is the resistance below 100 Ohms?
Yes
- Repair the short to ground in the (K126) ETC Negative circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 9
9. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Throttle Body and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Throttle Body and Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module. Powertrain Control Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.