Intermittent Condition

INTERMITTENT CONDITION

Diagnostic Test

1. INTERMITTENT CONDITION
NOTE: The conditions that set the DTC are not present at this time. The following list may help in identifying the intermittent condition.

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.

Search for any Technical Service Bulletins (TSBs) that may apply.
Review the scan tool Freeze Frame information. If possible, try to duplicate the conditions under which the DTC set.
With the engine running at normal operating temperature, monitor the scan tool parameters related to the DTC while wiggling the wire harness. Look for parameter values to change and/or a DTC to set.
Turn the ignition off.
Visually inspect the related wire harness. Disconnect all the related harness connectors. Look for any chafed, pierced, pinched, partially broken wires and broken, bent, pushed out, or corroded terminals. Verify correct connector pin fit at the related connectors.
Perform a voltage drop test on the related circuits between the suspected inoperative component and the PCM.

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 Miller Special Tool #8815 to perform diagnosis.

Inspect and clean all PCM, engine, and chassis grounds that are related to the most current DTC.
If numerous trouble codes were set, use a wire schematic and look for any common ground or supply circuits.
For any Relay DTCs, actuate the Relay with the scan tool and wiggle the related wire harness to try to interrupt the actuation.
For intermittent Evaporative Emission trouble codes perform a visual and physical inspection of the related parts including hoses and the Fuel Filler cap.
For intermittent Misfire DTCs check for restrictions in the Intake and Exhaust system, proper installation of Sensors, vacuum leaks, and binding components that are run by the accessory drive belt.
Use the scan tool to perform a System Test if one applies to failing component.
A co-pilot, data recorder, and/or lab scope should be used to help diagnose intermittent conditions.
Were any problems found during the above inspections?

Yes

- Perform the necessary repairs.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Test Complete.