Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit/System Testing
2008 Pontiac Grand Prix BaseSECTION 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.
- Ignition OFF, disconnect the harness connectors at the PCM.
- Ignition OFF, test for less than 1.0 ohm between the ground circuit X2 terminal 73 to ground.
- If greater than the specified value, test the ground circuit for an open/high resistance.
- Ignition ON, measure between the Ignition 1 circuit X1 terminals 18-19 and the ground circuit X2 terminal 73. The readings should not differ by more than 2 volts than the battery terminal voltage.
- If greater than the specified value, test the Ignition 1 circuits for an open/high resistance.
- If the circuits test normal replace the PCM.
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.