Diagnostic Aids
WARNING: This page is about a different car, the 2002 Saturn LW200, 2002 Saturn L200, and 2002 Saturn L100. However, it is still accessible from the selected car via links, so may be relevant.
To locate an intermittent problem, use scan tool to monitor ECT and IAT temperature with ignition ON, engine OFF. Wiggling wires will watching for a change in ECT or IAT temperature may locate the area where a short to ground in wiring could lie.
An engine block heater may cause DTC to set.