When your Sierra 3500 isn’t running right, your work stops. A faulty Powertrain Control Module (PCM) is often the hidden culprit behind frustrating issues like poor performance, check engine lights, and even a truck that won’t start. This isn’t just an inconvenience; it’s a roadblock to getting the job done. Get your workhorse back in prime condition with our expertly programmed 2004 Sierra 3500 PCM, the reliable brain your truck needs to perform at its best.
Common Symptoms & Your Solution
If you’re experiencing any of the following, a failing PCM could be the cause. This pre-programmed module is the definitive solution to restore your truck’s dependability.
- Check Engine Light (CEL) with communication-related codes (e.g., P0601, P0606)
- Rough or inconsistent idling
- Poor fuel economy
- Hesitation or stalling during acceleration
- Transmission shifting issues
- Complete no-start condition
Instead of wrestling with a problematic module or paying steep dealership prices for programming, this unit offers a straightforward, effective fix. We take your vehicle’s VIN and flash this computer with the latest, most stable software from GM, ensuring it communicates perfectly with your truck’s specific systems right out of the box.
Features & Benefits
- ✔ Plug & Drive Installation: No complicated dealer visits. We program this module to your truck’s specific VIN, so it’s ready to install right out of the box. A simple security relearn procedure may be required, which you can do yourself in 15 minutes.
- ✔ Optimized Factory Performance: Flashed with the latest GM software updates to ensure peak engine efficiency, smooth shifting under load, and optimal fuel economy for your 8.1L or 6.0L engine.
- ✔ Guaranteed Compatibility: A direct replacement for part numbers 12586243 and 89017739, ensuring a perfect fit and function for your 2004 Sierra 3500 and many other GM vehicles.
- ✔ Solves Common Failures: Specifically addresses internal processor faults and communication errors that plague original modules, providing a lasting solution.
- ✔ Peace of Mind Protection: This unit is backed by our one-year replacement warranty.
An Expert’s Take: As a mechanic for over 20 years, I’ve seen countless issues caused by generic, non-programmed modules. A correctly flashed PCM isn’t just about starting the engine; it’s about making sure the transmission shifts correctly under load and the fuel system operates efficiently. For a work truck like the Sierra 3500, getting the programming right is the difference between a reliable workhorse and a constant headache. We handle that critical step for you, so you can install it with confidence and get back on the road.
Frequently Asked Questions
What information do you need from me?
After you place your order, we will need your vehicle’s 17-digit VIN (Vehicle Identification Number). This is essential for us to program the 2004 Sierra 3500 PCM with the correct software for your truck’s specific engine, transmission, and options.
Do I need to do anything after I install it?
In most cases on these GM trucks, you will need to perform a simple security relearn procedure, also known as the “Passlock Relearn.” This process pairs the new module to your vehicle’s anti-theft system. It doesn’t require any special tools and typically involves a sequence of turning the key on and off. We include simple instructions to guide you through it. A crankshaft variation relearn (CASE) may also be needed with a capable scan tool for optimal performance.
Is this a brand new part?
This is a high-quality, genuine GM module that has been meticulously inspected, tested, and prepared to ensure it meets or exceeds original factory standards. It is then programmed specifically for your vehicle.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of your original PCM (like a P0601 code), this module is designed to be the direct solution. However, it’s always crucial to ensure that the root cause of the problem is the computer itself and not a separate sensor or wiring issue. This 2004 Sierra 3500 PCM will resolve all internal computer faults.
Is this compatible with other GM vehicles?
Yes, this PCM, part number 12586243, was used across a very wide range of 2004 GM vehicles, including Silverado, Suburban, Express/Savana vans, Trailblazer, Corvette, and more. As long as your original part number matches, we can program it for your specific GM vehicle.
