Is Your 2004 GM Truck or SUV Acting Up?
If your 2004 GMC Yukon, Sierra, Silverado, or another compatible GM vehicle is suffering from erratic behavior, poor performance, or a persistent check engine light, a failing Powertrain Control Module (PCM) could be the culprit. The PCM is the central computer of your vehicle, responsible for managing everything from fuel injection and ignition timing to transmission shifting and emissions control. When it fails, it can cause a cascade of frustrating and difficult-to-diagnose issues, leaving your vehicle unreliable or even undrivable.
From the Diagnostic Bay
We had a 2004 Sierra 1500 come into the shop with what the owner was convinced was a failing transmission. It was shifting hard, hunting for gears, and occasionally throwing a check engine light for a torque converter circuit. He had already spent a small fortune at a transmission shop that couldn’t find anything mechanically wrong. After plugging in our scanner, we noticed erratic data from the PCM. Instead of a costly transmission rebuild, the solution was a simple, correctly programmed replacement PCM. The truck was shifting perfectly within an hour of the install. It’s a classic case of the vehicle’s brain causing symptoms that appear elsewhere.
Symptoms of a Failing 2004 Yukon PCM
A faulty engine computer can manifest in numerous ways. If you’re experiencing any of the following, it’s time to consider a replacement. Look out for:
- ✔ Check Engine Light is on with various trouble codes (DTCs).
- ✔ Vehicle fails to start or starts intermittently.
- ✔ Poor engine performance, including stalling, sputtering, or rough idling.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or incorrect automatic transmission shifting.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Seemingly unrelated electrical issues throughout the vehicle.
The Direct-Fit, Programmed Solution
This is a direct replacement PCM, service number 12586242, for a wide range of 2004 General Motors trucks and SUVs. To ensure a hassle-free installation, we program the module specifically for your vehicle using the VIN you provide. This critical step loads the latest GM-certified software and calibrations, matching your vehicle’s exact configuration and options. This means no expensive trips to the dealership for programming are necessary.
This module is compatible with and replaces the following service numbers: 12586242, 19299226, 89017738 and broadcast codes such as YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP, YHTN. By providing your VIN, you guarantee you receive a module that is 100% correct for your application, restoring factory performance and reliability.
Installation is straightforward for the DIY mechanic or any professional technician. On most compatible trucks and full-size SUVs like the Yukon, Sierra, and Silverado, the PCM is located in the engine bay on the driver’s side, under the battery tray. On models like the Trailblazer and Envoy, it is typically found next to the air filter box. Simply disconnect the battery, unbolt the old module, disconnect the wiring harnesses, and install the new one in its place. After installation, a simple security relearn procedure may be required, which can be done without any special tools.
Frequently Asked Questions
Do I need to do any programming after I install this PCM?
No. We flash the module with your vehicle’s specific VIN and the latest GM software before shipping. In most cases, you will only need to perform a simple security relearn procedure (often called a CASE relearn), which takes about 30 minutes and does not require any special tools. Instructions are readily available online for this process.
How do I provide my vehicle’s VIN?
After you complete your purchase, you can add your VIN to the ‘notes’ section of your order. If you forget, we will contact you via email to request it before we can program and ship your part. Your order will not ship until we have this information.
Is this the correct part for my vehicle?
This PCM fits a wide variety of 2004 GM models. The best way to confirm is to match the service number 12586242 from your original unit. However, providing us with your VIN is the most reliable method to guarantee you receive the exact part you need for your specific vehicle.
What if my original part number isn’t on the list?
If your part number is different, please contact us with your VIN before ordering. GM uses many interchangeable part numbers, and we can verify compatibility to ensure you get the right component for your truck or SUV.
What tools are needed for installation?
Basic hand tools are all that’s required for the physical installation, typically a socket set to remove the mounting bolts and disconnect the battery terminal. No special diagnostic equipment is needed.