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.
2008 Pontiac Grand Prix BaseFACTORY OEM SERVICE PROCEDURE
Control Units
CONTROL UNITS LOCATION
| Component | Location |
|---|---|
| Blower Motor Control Processor (3) | Lower right side HVAC module. See Figure. |
| Body Control Module (BCM) (3) | Behind left side of dash, left of steering column. See Figure. |
| Digital Radio Receiver (7) | Left side of rear compartment. See Figure. |
| Electronic Brake Control Module | Left side of engine compartment, part of brake pressure modulator valve. See Figure. |
| Electronic Compass Module | Top center of rear package shelf. See Figure. |
| HDM MODULE | In underhood fuse block. See Figure. |
| Ignition Control Module (ICM) (1) | Top left front of engine. See Figure. |
| Inflatable Restraint Sensing & Diagnostic Module (SDM) | Under right front seat. See Figure. |
| Powertrain Control Module (PCM) (3.8L) | Left front side of engine compartment, in air cleaner assembly. See Figure. |
| Powertrain Control Module (5.3L) | Left side of engine compartment, inside air cleaner assembly. See Figure. |
| Radio Antenna Module | Center rear of roof. See Figure. |
| Theft Deterrent Exciter Module | Part of ignition key cylinder. See Figure. |
| Throttle Actuator Control (TAC) Module (3.8L) (7) | On throttle body. See Figure. |
| Throttle Actuator Control (TAC) Module (5.3L) | Top rear of engine. See Figure. |
| Transmission Control Module | Left side of engine compartment, inside air cleaner assembly. See Figure. |
| Vehicle Communications Interface Module (VCIM) (7) | In trunk, on left wheelwell. See Figure. |
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no 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.