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
- Ignition OFF, disconnect the inside rearview mirror harness connector.
- Ignition ON, test for 9.2-10.2 volts on the keypad supply voltage circuit terminal 12.
- If less than the specified voltage repair short to ground or open or replace the VCIM.
- Test for less than 1 ohm between the inside rearview mirror harness connector terminal 8 and ground.
- If greater than specified value repair open or high resistance.
- Connect a DMM between the inside rearview mirror harness connector terminal 14 and ground. With a scan tool command the green LED ON. Verify 9.2-10.2 volts is present with the green LED commanded ON.
- If 9.2-10.2 volts is present with the green LED is commanded ON, replace the inside rearview mirror.
- Connect a DMM between the inside rearview mirror harness connector terminal 15 and ground. With a scan tool command the red LED ON. Verify 9.2-10.2 volts is present with the red LED commanded ON.
- If 9.2-10.2 volts is present with the red LED is commanded ON, replace the inside rearview mirror.
- Disconnect the VCIM harness connector X1.
- Test for less than 1 volt between the X1 VCIM connector terminal 3 and the inside rearview mirror harness connector terminal 14.
- If more than the specified value repair short to voltage on the keypad green LED signal circuit.
- Test for less than 1 volt between the X1 VCIM connector terminal 2 and the inside rearview mirror harness connector terminal 15.
- If more than the specified value repair short to voltage on the keypad red LED signal circuit.
- Test for less than 1 ohm between the X1 VCIM connector terminal 3 and the inside rearview mirror harness connector terminal 14.
- If more than the specified value repair open or high resistance on the keypad green LED signal circuit.
- Test for less than 1 ohm between the X1 VCIM connector terminal 2 and the inside rearview mirror harness connector terminal 15.
- If more than the specified value repair open or high resistance on the keypad red LED signal circuit.
- If all circuits test normal, test or replace the VCIM.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.