Restore Your Truck’s Power and Reliability
Is your 2004 GMC Sierra 3500 running rough, shifting erratically, or failing to start? A faulty Powertrain Control Module (PCM) can bring your workhorse to a grinding halt, costing you valuable time and money. Get back on the job fast with this reliable, VIN-programmed replacement engine computer that restores your truck’s original performance and dependability. This is the definitive solution to get your vehicle running right again, without the hassle and expense of a dealership visit.
Common Symptoms & Your Solution
If your truck is experiencing any of the following issues, a failing PCM is the likely culprit. This pre-programmed module is designed to be the direct solution for these frustrating problems:
- Harsh or unpredictable transmission shifting
- Engine misfires or stumbling
- Complete no-start or intermittent starting condition
- Poor fuel economy
- Check Engine Light with codes like P0601, P0602, P0606, or other communication errors
Our process is simple: you provide your vehicle’s VIN during checkout, and we program the 2004 GMC Sierra 3500 PCM 12586242 with the latest GM software updates specific to your truck. It arrives at your door ready for installation, saving you from needing expensive proprietary scan tools.
Features & Tangible Benefits
- โ VIN-Programmed for Your Truck: We flash this module with your vehicle’s specific VIN and the latest GM software updates, ensuring a perfect match and optimal performance right out of the box.
- โ Simple, Hassle-Free Installation: Because it arrives fully programmed, this PCM eliminates the need for dealership appointments. It’s designed for a straightforward installation to get you back on the road quickly.
- โ Restores Peak Performance: Corrects common issues like rough idling, poor fuel mileage, and erratic shifting, bringing back the reliable power you depend on for towing and hauling.
- โ Direct Fit Guarantee: This unit is a direct replacement for service number 12586242 and other compatible numbers listed, ensuring a perfect physical fit in your 2004 GMC Sierra 3500.
- โ Coverage You Can Count On: This unit is backed by our one-year replacement warranty.
Expert Technician’s Insight
As a technician with over two decades of experience, I’ve seen countless engine computers replaced only to have the same problems persist. The issue wasn’t the part; it was the programming. A generic, unprogrammed module can’t communicate correctly with your truck’s other systems. That’s why we insist on programming every single 2004 GMC Sierra 3500 PCM 12586242 to your specific VIN. It’s not just about selling a part; it’s about providing a complete, lasting solution that gets you back on the road with confidence.
Frequently Asked Questions
What information do I need to provide for programming?
After you complete your purchase, you will need to provide us with your vehicle’s 17-digit Vehicle Identification Number (VIN). This is essential for us to program the module correctly for your specific truck.
Is this a true plug-and-play part?
Because this PCM comes fully programmed to your VIN, it is as close to plug-and-play as possible. In many cases, it will start and run the vehicle immediately. However, some GM vehicles may require a simple security relearn procedure (often called a CASE relearn or anti-theft relearn), which can typically be done without special tools. Instructions are readily available online for this process.
How can I confirm this is the right part for my vehicle?
The best way is to match the service number on your current PCM. This module replaces part number 12586242 and the other service numbers listed in the description. Please check the fitment list or contact us with your VIN if you are unsure.
Will this fix my check engine light?
If the check engine light is on due to an internal failure of the original PCM (like with code P0601), then this replacement will solve the problem. It’s crucial to ensure all other potential issues (e.g., bad sensors, wiring problems) have been ruled out by proper diagnostics before replacing the computer.
What is the warranty on this PCM?
This unit is backed by our one-year replacement warranty, giving you confidence in your repair.
Does this fit vehicles other than the Sierra 3500?
Yes, this 2004 GMC Sierra 3500 PCM 12586242 fits a wide range of 2004 GM trucks and SUVs, including the Silverado, Tahoe, Suburban, Yukon, Escalade, and more. Please refer to the detailed fitment list on this page to confirm compatibility with your specific model.