Circuit/System Testing

WARNING: This page is about a different car, the 2007 Pontiac G5 Pursuit, 2007 Pontiac G5, and 2007 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.

P0325, P0327 and P0328

IMPORTANT: If the KS lead is damaged in any way, replace the KS.

Ignition ON, engine OFF.
Disconnect the KS harness connector.
Measure for 2-3 volts between each of the following circuits and ground on the engine control module (ECM) side of the harness connector:
- The KS signal circuit, terminal A
- The KS signal circuit, terminal B
- If less than the specified range, test the circuits for a short to ground or an open/high resistance. If the circuits test normal, replace the ECM.
- If greater than the specified range, test the circuits for a short to voltage. If the circuits test normal, replace the ECM.
If the circuits test normal, replace the KS.

P0326

IMPORTANT: If DTC P0327, P0328, P0335, P0336 are also set, diagnose those DTCs first.

Inspect for a loose or broken vehicle accessory or accessory bracket.
Inspect for excessive engine mechanical noise.