Circuit/System Testing
WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
Do not turn the key to the crank position or engage the starter at any time during diagnosis.
- Ignition OFF, disconnect the harness connector at the EOP switch.
- Ignition OFF, test for less than 1 ohm of resistance between the ground circuit terminal B and ground.
- If greater than the specified value, test the ground circuit terminal B for an open/high resistance.
- Ignition ON, install a 3A fused jumper wire between the signal circuit terminal A and the ground circuit terminal B. Verify the scan tool Engine Oil Pressure Switch parameter is Low.
- If not Low, test the signal circuit terminal A for a short to voltage or an open/high resistance. If the circuit tests normal, replace the PCM.
- If all circuits test normal, replace the engine oil pressure switch.