Diagnostic Aids
WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
Check for any of the following conditions:
A DTC P0641 can set when water shorts the reference circuit high or low. Inspect for water entry into the sensor or PCM electrical connectors.
An intermittent malfunction may be caused by a fault in the 5-volt reference 1 electrical circuit. Inspect the wiring harness and the components for an intermittent condition. Refer to Intermittent Conditions .
If the DTC P0641 cannot be duplicated, the information included in the Freeze Frame data can be useful in determining vehicle operating conditions when the DTC was first set.