Restore Peak Performance to Your Cadillac or Pontiac
Is your 2004-2005 Cadillac DeVille, Seville, or Pontiac Bonneville suffering from perplexing issues like a persistent check engine light, rough idling, stalling, or poor fuel economy? These are classic signs of a failing Powertrain Control Module (PCM), the central computer that governs your vehicle’s engine and transmission. Don’t let a faulty module keep your luxury vehicle off the road. This genuine, used GM PCM, part number 12587465, is the reliable and cost-effective solution you need to get back in the driver’s seat with confidence.
The Brain of Your Northstar V8 Engine
The PCM is arguably the most critical electronic component in your vehicle. It continuously analyzes data from dozens of sensors to manage fuel injection, ignition timing, transmission shift points, and emissions systems. When it fails, the entire powertrain can behave erratically, leading to frustrating and potentially damaging symptoms. Replacing it with a generic, unprogrammed unit from a local parts store can lead to compatibility issues and a car that still won’t start. Our solution eliminates that guesswork.
Expert Pro Tip
Before condemning your PCM, always perform a full diagnostic check. Ensure your vehicle’s battery is fully charged and passes a load test. Also, inspect the main engine and chassis ground connections for corrosion or looseness. A poor ground or unstable voltage can often mimic the symptoms of a failed PCM, and checking these simple items first can save you time and money.
Common Symptoms of a Failing 2004-2005 DeVille PCM
If you’re experiencing any of the following issues, a faulty PCM is a likely culprit. This module is your direct solution to these common problems:
- ✔ Persistent Check Engine Light (CEL) with communication-related trouble codes (e.g., U-codes).
- ✔ Engine stalling unexpectedly or for no apparent reason.
- ✔ Difficulty starting the engine, or a complete no-start condition where the engine cranks but won’t fire.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Engine misfires, stumbling, or hesitation during acceleration.
- ✔ Failure to pass state emissions testing.
Plug-and-Play Solution with VIN Programming
What sets this PCM apart is our professional programming service. This isn’t just a part off a shelf; it’s a component fully prepared for your specific vehicle. When you purchase, you simply provide us with your vehicle’s 17-digit VIN. Our technicians will then flash the module with the latest GM-certified software and calibrations that match your car’s exact configuration. This critical step ensures seamless communication with your vehicle’s other modules, eliminating the need for expensive dealership programming. While the PCM will be pre-programmed, you will need to perform a simple security relearn procedure upon installation to sync the module with your car’s anti-theft system. This can typically be done in your own driveway without any special tools.
Guaranteed Fitment
This Electronic Control Module is a direct replacement for service numbers 12587465, 12586547, and 15576920. It is guaranteed to fit the following vehicles:
- 2004-2005 Pontiac Bonneville (with 4.6L engine)
- 2005 Cadillac DeVille (with ID 12587465)
- 2004 Cadillac DeVille
- 2004 Cadillac Seville
Frequently Asked Questions
Do I need to program this PCM?
No. We handle the programming for you before shipment. All you need to do is provide your vehicle’s VIN during or after checkout. This ensures the module is ready for your specific vehicle configuration.
What is the ‘security relearn’ procedure?
The security relearn, or anti-theft relearn, syncs the new PCM to your car’s keys. It’s a simple procedure you can do yourself. Typically, it involves turning the key to the ‘ON’ position for 10 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. Your vehicle’s manual will have the exact instructions.
Is this a new part?
This is a high-quality, tested, and fully functional used part sourced from a salvaged vehicle. Every unit is inspected to ensure it meets our standards, providing a reliable and affordable alternative to a costly new module from a dealership.
Will this fix my car’s problem for sure?
This PCM will resolve any issues directly caused by a faulty control module. However, it’s crucial that your vehicle has been properly diagnosed. This part cannot fix problems originating from other failed components like sensors, wiring, or mechanical parts.
Where is this module located on my vehicle?
For the compatible Cadillac and Pontiac models listed, the Powertrain Control Module is located in the engine compartment on the left-hand (driver’s) side, typically inside the air filter housing assembly.