Is Your 2004 GM Truck or SUV Running Rough?
If you’re dealing with perplexing engine issues in your 2004 Chevrolet Suburban 2500, GMC Sierra, or another compatible GM vehicle, a failing Powertrain Control Module (PCM) is often the culprit. This central computer is the brain of your engine, managing everything from fuel mixture and ignition timing to transmission shifting and emissions control. When it starts to fail, it can cause a cascade of problems that are difficult to diagnose, leading to wasted time and money on unnecessary repairs.
This is a direct replacement PCM, service number 12586242, designed to restore your vehicle’s performance and reliability. We take the guesswork out of the repair by programming the module specifically to your vehicle’s VIN before it ships. This ensures seamless integration and proper communication with all other onboard systems, getting you back on the road quickly and confidently.
From the Diagnostic Bay
We had a 2004 Silverado 2500 come in with a persistent random misfire code (P0300) and a harsh 1-2 shift. The owner had already replaced the spark plugs, wires, and even a couple of ignition coils with no luck. After connecting our diagnostic scanner, we noticed erratic data from several key sensors, but the sensors themselves tested fine. This pointed us directly to the PCM. The internal processors were failing, sending corrupt data throughout the system. We installed a VIN-programmed 2004 Suburban 2500 PCM (the same unit fits the Silverado), performed the security relearn, and the truck ran perfectly. It’s a classic case where the central component was the root cause, mimicking other failures.
Symptoms of a Failing 2004 GM PCM
- ✔ Check Engine Light is on with various or no specific codes.
- ✔ Vehicle fails to start or stalls intermittently.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Engine misfires, stumbles, or hesitates during acceleration.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Inaccurate or non-functional dashboard gauges.
Why Choose Our Pre-Programmed 2004 Suburban 2500 PCM?
This isn’t just a generic, off-the-shelf part. It’s a complete solution. By providing us with your Vehicle Identification Number (VIN) during checkout, you receive a module that is loaded with the latest GM-certified software specifically for your vehicle’s configuration. This critical step ensures that all factory parameters for your engine, transmission, and options are correctly calibrated. The result is a simple, plug-and-play installation process that eliminates the need for expensive dealership programming.
This module is a direct replacement for service number 12586242 and is also compatible with a wide range of other service numbers, including: 19299226, 89017738, YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP, and YHTN. It fits a vast array of 2004 GM models such as the Chevrolet Silverado, Tahoe, Avalanche, SSR; GMC Sierra, Yukon; Cadillac Escalade; Hummer H2; Buick Rainier; and more. Please verify your part number to ensure proper fitment.
Installation is straightforward for any DIY mechanic. Simply disconnect the battery, locate your old PCM (typically under the hood on the driver’s side, beneath the battery tray), swap the connectors, and install the new unit. After installation, you will need to perform a simple security relearn procedure, which can be done without any special tools. This procedure pairs the new PCM to your vehicle’s anti-theft system.
Frequently Asked Questions
Do I have to provide my VIN?
Yes, providing your vehicle’s 17-digit VIN is mandatory. We use it to load the correct, updated software from GM for your specific vehicle, which ensures proper function and a smooth installation process.
Is any additional programming required after installation?
No dealership programming is needed. However, you must perform a security relearn procedure to sync the new PCM with your vehicle’s anti-theft system. This typically involves a series of key turns and waiting periods and can be done in your driveway without special tools.
Will this fix my transmission shifting problems?
If the harsh or erratic shifting is caused by a faulty PCM, then yes, this part will resolve the issue. The PCM controls transmission line pressure and shift points, so a failing module is a common cause of these symptoms.
Where is the PCM located on my 2004 Suburban?
On most 2004 GM full-size trucks and SUVs like the Suburban, Silverado, and Sierra, the PCM is located on the driver’s side of the engine bay, mounted in a black plastic bracket underneath the battery tray.
How do I confirm this is the right part for my vehicle?
The best way is to match the service number on your current PCM to one of the compatible numbers listed, with 12586242 being the primary part number. If you are unsure, please contact us with your VIN, and we can verify fitment for you.