Is Your Grand Prix Running Rough? The PCM Might Be the Culprit.
If you’re dealing with a persistent check engine light, erratic engine behavior, poor fuel mileage, or even a no-start condition in your 2003 Pontiac Grand Prix, a failing Powertrain Control Module (PCM) is a very common cause. As a technician with over two decades of experience, I’ve seen these symptoms countless times. The PCM is the brain of your vehicle’s engine and transmission, and when it starts to fail, it can create a cascade of frustrating and hard-to-diagnose problems.
The Simple, Reliable Solution: A VIN-Programmed PCM
Forget expensive dealership visits and the hassle of finding a local shop that can program a new module. We provide a straightforward solution. This Powertrain Control Module, part number 89017735, arrives at your door fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We load the latest, most stable software updates from GM, ensuring optimal performance and compatibility right out of the box. This isn’t just a replacement part; it’s a direct fix for the core electronic issues plaguing your car.
Expert Pro Tip: Check for Corrosion Before You Install
In my shop, a common issue I find on these GM W-body platforms (like the Grand Prix, Impala, and Regal) is water intrusion. Before you even unbolt the old PCM, take a close look at the wiring harness connectors. Unplug them and inspect the pins for any signs of green or white corrosion. Water can wick down the harness and compromise the connection, causing many of the same symptoms as a bad module. Cleaning the connector terminals with a small brush and electrical contact cleaner can prevent future issues and ensure your new 2003 Grand Prix PCM communicates perfectly from the start.
Plug-and-Play Installation: No Dealer Visit Required
We’ve made this process as simple as possible. Because we program the module with your VIN before shipping, it bypasses the complex anti-theft (VATS/PASS-Key) systems, eliminating the need for a costly trip to the dealer for programming. You can perform this replacement right in your own driveway.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: On your 2003 Grand Prix, the PCM is located in the engine compartment on the driver’s side (LH side), typically housed within the air filter box assembly.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old module. Press the release tabs firmly. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Seat the new PCM into the bracket and secure it. Firmly reconnect the wiring harnesses, ensuring they click into place.
- Reconnect Power: Reattach the negative battery terminal. The vehicle is now ready to start.
Guaranteed Compatibility and Performance
This module is a direct replacement for service numbers 89017735 and 12583826. When you purchase, simply provide us with your vehicle’s VIN, and we handle the rest. You’ll receive a part that restores factory function and drivability.
- ✔ Fixes common issues like stalling, rough idle, and false sensor codes.
- ✔ Programmed with your VIN for seamless integration.
- ✔ Loaded with the latest GM software for improved performance and efficiency.
- ✔ Eliminates the need for dealer-specific programming tools.
- ✔ A cost-effective and reliable repair for your vehicle.
Vehicle Fitment Information
This 2003 Grand Prix PCM is also a direct fit for a range of other GM vehicles. Please verify your vehicle and options below. The ID number is often printed on the original module’s sticker.
- Bonneville: 2003 (LH engine compartment, ID 12583826)
- Grand Prix: 2003 (3.8L, LH front engine compartment, ID 12583826)
- Impala: 2003 (3.8L, LH engine compartment, ID 12583826 or 89017735)
- LeSabre: 2003 (LH engine compartment, ID 12583826)
- Monte Carlo: 2003 (3.8L, LH engine compartment, ID 12583826)
- Park Avenue: 2003-2004 (LH front engine compartment, check ID for 2004)
- Regal: 2003-2004 (LH engine compartment)
Don’t let a faulty computer keep you off the road. Order today and restore your car’s proper function and reliability.