Diagnostic Aids
WARNING: This page is about a different car, the 2002 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
If DTC P1635 is also set, a short to ground on 5-volt reference circuit may exist. Diagnose P1635 first. See DTC P1635: 5-VOLT REFERENCE 1 CIRCUIT .
If actual A/C pressure (measured with gauge) matches scan tool reading, repair any A/C problem before proceeding with this DTC. ECM will disable A/C clutch when this DTC is set.
To locate an intermittent problem, use scan tool to monitor A/C HIGH SIDE PRESS. SENSOR voltage with ignition on, engine off. Wiggling wires while watching for a change in A/C HIGH SIDE PRESS. SENSOR voltage may locate area where an open, short to ground or short to voltage in wiring could lie.
ECM will disable A/C relay is DTC P0530 is active.