Diagnostic Aids

WARNING: This page is about a different car, the 2003 Saturn Vue and 2002 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

To locate an intermittent problem, use a scan tool to monitor OSS with the engine running. Wiggling wires while watching for a change in the OSS parameter may locate the area where an open in the wiring may lie. In addition, check for loose terminal connections. DTC P0723 can set due to the following:

Intermittent open anywhere in the OSS circuit.
Intermittent short to ground or short to voltage OSS circuit.
Loose sensor.
Inoperable sensor.
Electromagnetic interference caused by high current carrying wiring routed near OSS sensor wiring.