Diagnostic Aids
WARNING: This page does not describe the selected car, but rather 11 other vehicles, including the 2002 GMC Yukon XL, 2002 GMC Yukon, 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, and 2002 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Before servicing the powertrain control module/throttle-actuated control (PCM/TAC), remove any debris from module connector surfaces. Inspect the PCM/TAC module connector gaskets when diagnosing or replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the PCM/TAC modules.
For any test that requires probing the PCM or a component harness connector, use the J 35616-A Connector Test Adapter Kit. Using this kit prevents damage to the harness or the component terminals.
The following problems may cause this DTC to set:
- Poor connections.
- Crankshaft reluctor wheel damage or improper installation.
- The sensor coming in contact with the reluctor wheel.
- The engine running out of fuel.
- If the crankshaft rotates backwards, this DTC sets. This condition is only with vehicles equipped with a manual transmission. This condition can occur when a vehicle is on an incline and the clutch is released and an engine stall occurs.
Excess crankshaft end play will cause the CKP sensor reluctor wheel to move out of alignment with the CKP sensor. This could result in any one of the following conditions:
- A no-start
- A start and stall
- Erratic performance
For an intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.