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.
Component Testing
2008 Pontiac Grand Prix BaseSECTION Component Testing
WARNING: This page is about a different car, the 2008 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.
Multifunction Switch
- Ignition OFF, disconnect the X3 harness connector at the turn signal/multifunction switch.
- Test the resistance between terminals M and N. Rotate the wiper switch and compare the resistance readings to the values in the Windshield Wiper Switch Values table below for MIST, each DELAY and LOW speed.
- If the resistance is not within the specified range, replace the turn signal/multifunction switch.
- Test for infinite resistance between terminals M and K while rotating the wiper switch to MIST, each DELAY and LOW speed positions.
- If the less than infinite, replace the turn signal/multifunction switch.
- Test for less than 5 ohms of resistance with the wiper switch in the High speed position..
- If greater than 5 ohm, replace the turn signal/multifunction switch.
- Test for infinite resistance between terminals M and L while rotating the wiper switch to MIST, each DELAY and LOW speed positions.
- If less than infinite, replace the turn signal/multifunction switch.
- Test for less than 5 ohm of resistance while pressing the WASHER switch.
- If greater than 5 ohm, replace the turn signal/multifunction switch.
IMPORTANT:
If the switch tests open in any switch position other than Off, test the wiper/washer switch signal circuits for a short to voltage before replacing the switch.
Wiper Switch Values
| Switch Position | Resistance |
|---|---|
| Off | Infinite |
| Mist | 300-364 Ω |
| Delay 1 | 3.48K-4.25K Ω |
| Delay 2 | 2.52K-3.08K Ω |
| Delay 3 | 1.78K-2.18K Ω |
| Delay 4 | 1.17K-1.44K Ω |
| Delay 5 | 697-851 Ω |
| Low | 300-364 Ω |
Windshield Wiper Motor Dynamic Test
- Ignition OFF, disconnect the harness connector at the windshield wiper motor.
- Install a 25-amp fused jumper wire between the control terminal 1 and 12 volts. Install a jumper wire between the ground terminal 5 and ground.
- The wiper motor should be in low speed mode.
- If the wiper motor is not in the low speed mode replace the motor.
- Install a 25-amp fused jumper wire between the control terminal 4 and 12 volts. Install a jumper wire between the ground terminal 5 and ground.
- The wiper motor should be in the high speed mode.
- If the wiper motor is not in the high speed mode replace the motor.
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.