Restore Peak Performance to Your 2004 GM Vehicle
Is your 2004 Chevrolet Express 3500, GMC Savana, or other compatible GM vehicle suffering from perplexing issues like a persistent check engine light, erratic shifting, poor fuel economy, or a no-start condition? The Powertrain Control Module (PCM), the electronic brain of your vehicle, is often the culprit. This vital component manages everything from fuel injection and ignition timing to transmission shift points and emissions controls. When it fails, the symptoms can be widespread and frustrating. This replacement PCM, part number 12586243, is the definitive solution to restore your vehicle’s original performance and reliability.
The Importance of a VIN-Programmed Module
You can’t simply swap a PCM from another vehicle and expect it to work. Each module is programmed with software specific to a vehicle’s Vehicle Identification Number (VIN). This programming accounts for the engine size, transmission type, emissions equipment, and other factory-installed options. Our process ensures you receive a module that is a perfect electronic match for your vehicle. We flash it with the latest official GM software updates, which often correct factory bugs and improve overall performance and longevity. This means you get a plug-and-play solution without needing an expensive trip to the dealership for programming.
Diagnosing a Failing 2004 Express 3500 PCM
A failing powertrain computer can manifest in numerous ways. If you’re experiencing any of the following symptoms, a faulty PCM is a likely cause. This module is the correct replacement for a wide range of 2004 GM trucks, vans, and SUVs, including the Silverado, Sierra, Suburban, and Trailblazer. Always confirm your part number (12586243 or 89017739) before ordering.
Common Symptoms of a Bad PCM
- ✔ Check Engine Light is on with various, often unrelated, trouble codes (DTCs).
- ✔ Vehicle fails to start or starts intermittently.
- ✔ Noticeable decrease in fuel efficiency for no apparent reason.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Engine stalling, stumbling, or misfiring while driving.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Failure to pass state emissions testing.
Simple, Reliable Installation Process
Once you receive your pre-programmed PCM, the installation process is straightforward for a DIY mechanic or any professional technician. After providing us with your VIN during the checkout process, we handle all the complex programming. Your module arrives ready to be installed. Simply disconnect the battery, locate and remove your old module, install the new one, reconnect the battery, and perform any necessary security or idle relearn procedures as specified for your vehicle. This eliminates the need for specialized tools or software, getting you back on the road faster.
Frequently Asked Questions
Do I need to send you my old PCM?
No, there is no core charge or need to send your original module to us. This is an outright purchase.
What information do you need from me?
After you place your order, you must provide us with your vehicle’s 17-digit VIN. This is crucial for us to program the module correctly for your specific engine, transmission, and options.
Is any additional programming required after installation?
In most cases, no additional programming is needed. However, some GM vehicles may require a security relearn procedure (often called a CASE relearn or Passlock relearn) which can typically be done without special tools. Instructions are widely available online for specific models.
How do I find the PCM on my 2004 Express Van?
On the 2004 Express and Savana vans, the Electronic Control Module is typically located in the engine compartment on the driver’s side, towards the rear of the compartment. Always disconnect the battery before attempting to remove or install the module.
Is this compatible with part number 89017739?
Yes, this module is a direct, compatible replacement for service numbers 12586243 and 89017739, covering a wide range of 2004 GM vehicles.