Diagnostic Test
- READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR DTC TO RETURN
- With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
- For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
- With the scan tool, erase all DTCs.
- Turn the ignition off for a minimum of 10.0 seconds.
- Turn the ignition on.
- Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
- With the scan tool, read DTCs.
Did the DTC return?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
- PERFORM AN INSPECTION OF THE THROTTLE BODY FOR FOREIGN MATERIAL, SCORING, OR OTHER DAMAGE THAT COULD CAUSE THE THROTTLE PLATE TO STICK
- Turn the ignition off.
- Remove the Air Cleaner Assembly from the Throttle Body.
- Check for any signs of a foreign material (ice, dirt, or excessive carbon build up) on the Throttle Plate or in the bore causing the Throttle Plate to stick.
Were any signs of foreign material or scoring of the throttle plate or bore found?
Yes
- Remove the debris if possible 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 POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 3
- CHECK THE AIR FILTER FOR RESTRICTIONS
- Remove and inspect the Air Filter.
Is the Air Filter dirty?
Yes
- Replace the Air Filter.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 4
- Remove and inspect the Air Filter.
- CHECK FOR CONTAMINATED FUEL
- Inspect the Fuel for contamination (Dirt, water, or other foreign material).
Is the fuel contaminated?
Yes
- Drain the Fuel from the Fuel Tank into an approved gas holding tank and add clean fuel. Refer to DRAINING FUEL TANK .
No
- Go To 5
- Inspect the Fuel for contamination (Dirt, water, or other foreign material).
- ISOLATE AND CHECK THE THROTTLE BODY (K124) MOTOR (+) CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- The ignition must be off when checking the continuity of a circuit.
- Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note: Use the wiring diagram as a guide to follow the path of the circuit.
- Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note: The meter leads can add resistance to the measurement value.
- Connect one lead of the DVOM to the circuit being tested at the component harness connector.
- Connect the other lead to the circuit being tested at the GPEC Adaptor and measure the resistance of the circuit.
- If it is necessary to probe a terminal at a PCM harness connector, connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM harness connector.NOTE:
The GPEC Diagnostic Adaptor can add up to 1.5 Ohms of resistance to the circuit.
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 GPEC Diagnostic Adaptor to perform the diagnosis.
Is the resistance below 3.0 Ohms?
Yes
- Go To 6
No
- Repair the circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- ISOLATE AND CHECK THE THROTTLE BODY (K126) MOTOR (-) CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- The ignition must be off when checking the continuity of a circuit.
- Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note: Use the wiring diagram as a guide to follow the path of the circuit.
- Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note: The meter leads can add resistance to the measurement value.
- Connect one lead of the DVOM to the circuit being tested at the component harness connector.
- Connect the other lead to the circuit being tested at the GPEC Adaptor and measure the resistance of the circuit.
- If it is necessary to probe a terminal at a PCM harness connector, connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM harness connector.NOTE:
The GPEC Diagnostic Adaptor can add up to 1.5 Ohms of resistance to the circuit.
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 GPEC Diagnostic Adaptor to perform the diagnosis.
Is the resistance below 3.0 Ohms?
Yes
- Go To 7
No
- Repair the circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- CHECK THE THROTTLE BODY MOTOR FOR PROPER OPERATION
- Turn the ignition off.
- Connect the Throttle Body harness connector.
- Measure the resistance of the ETC Motor by probing the GPEC Adaptor across the Throttle Body (K124) Motor (+) circuit and the Throttle Body (K126) Motor (-) circuit.
Is the resistance between 2.5 and 25.0 Ohms at closed throttle?
Yes
- Go To 8
No
- Verify that there is good pin to terminal contact in the Throttle Body and Powertrain Control Module connectors. Replace the Throttle Body Assembly if no problems were found in the connectors. Disconnect the Battery when replacing the Throttle Body Assembly. After installation is complete, use a scan tool and select the ETC RELEARN function. Refer to THROTTLE BODY, REMOVAL AND INSTALLATION .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- CHECK RELATED PCM AND COMPONENT HARNESS CONNECTIONS
- Disconnect all PCM harness connectors.
- Disconnect all related in-line harness connections (if equipped).
- Disconnect the related component harness connectors.
- Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
- Proper connector installation.
- Damaged connector locks.
- Corrosion.
- Other signs of water intrusion.
- Weather seal damage (if equipped).
- Bent terminals.
- Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
- Terminals that have been pushed back into the connector cavity.
- Check for spread terminals and verify proper terminal tension.
Repair any conditions that are found.
- Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
- Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
- Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
- With the scan tool, erase DTCs.
- Test drive or operate the vehicle in accordance with the when monitored and set conditions.
- With the scan tool, read DTCs.
Did the DTC return?
Yes
- Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL AND INSTALLATION, 3.6L (GPEC 2A) .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- The wiring or poor connection problem has been repaired.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .