Diagnostic Test
- 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.
- 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.
- 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
- Refer to STANDARD PROCEDURE and perform the INTERMITTENT CONDITION diagnostic procedure.
- Ignition on, engine not running.
- THROTTLE PLATE STUCK OPEN
- 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.
- Remove the Air Cleaner Assembly from the Throttle Body. Refer to BODY, AIR CLEANER, REMOVAL .
- Check for any signs of a foreign material causing the Throttle to remain open.
- Using a scan tool, under System Tests, perform the ETC Throttle Follower Test.
- 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. Refer to 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.
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.
- Turn the ignition off.
- TP SENSOR NO. 1 AND TP SENSOR NO. 2 BOTH EQUAL 2.5 VOLTS
- 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.
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.
No
- Go To 4.
- With a scan tool, perform the ETC Throttle Follower test while reading both TP Sensor voltage readings.
- (K124) ETC MOTOR (+) CIRCUIT SHORTED TO VOLTAGE
- Turn the ignition off.
- Disconnect the Throttle Body harness connector.
- Disconnect the PCM C2 harness connector.
- Ignition on, engine not running.
- Measure the voltage on the (K124) ETC Motor (+) circuit at the Throttle Body harness connector.
Is there any voltage present?
Yes
- Repair the short to voltage on the (K124) ETC Motor (+) circuit.
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.
No
- Go To 5.
- (K124) ETC MOTOR (+) CIRCUIT OPEN
- Turn the ignition off.
- Measure the resistance of the (K124) ETC Motor (+) circuit from the Throttle Body harness connector to the PCM C2 harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 6.
No
- Repair the open in the (K124) ETC Motor (+) circuit.
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.
- (K126) ETC MOTOR (-) CIRCUIT OPEN
- Measure the resistance of the (K126) ETC Motor (-) circuit from the Throttle Body harness connector to the PCM C2 harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 7.
No
- Repair the open in the (K126) ETC Motor (-) circuit.
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.
- Measure the resistance of the (K126) ETC Motor (-) circuit from the Throttle Body harness connector to the PCM C2 harness connector.
- (K124) ETC MOTOR (+) CIRCUIT SHORTED TO GROUND
- Measure the resistance between ground and the (K124) ETC Motor (+) circuit at the Throttle Body harness connector.
Is the resistance below 100 Ohms?
Yes
- Repair the short to ground in the (K124) ETC Motor (+) circuit.
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.
No
- Go To 8.
- Measure the resistance between ground and the (K124) ETC Motor (+) circuit at the Throttle Body harness connector.
- (K126) ETC MOTOR (-) CIRCUIT SHORTED TO GROUND
- Measure the resistance between ground and the (K126) ETC Motor (-) circuit at the Throttle Body harness connector.
Is the resistance below 100 Ohms?
Yes
- Repair the short to ground in the (K126) ETC Motor (-) circuit.
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.
No
- Go To 9.
- Measure the resistance between ground and the (K126) ETC Motor (-) circuit at the Throttle Body harness connector.
- 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. Verify that there is good pin to terminal contact in the Throttle Body and Powertrain Control Module connectors.
- Perform any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.
No
- Replace and program the Powertrain Control Module in accordance with the service information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
- Refer to STANDARD PROCEDURE and perform the POWERTRAIN VERIFICATION TEST.