Restore Peak Performance to Your 2004 GM Truck or SUV
Is your 2004 Yukon XL 2500, Sierra, or Escalade suffering from erratic behavior, poor fuel economy, or a persistent Check Engine Light? These are classic signs of a failing Engine Control Module (ECM). As the central computer of your vehicle, the ECM is responsible for managing everything from fuel injection and ignition timing to transmission shifting. When it falters, the entire vehicle’s performance and reliability are compromised. This replacement ECM, part number 12586242, is the definitive solution to get your vehicle running smoothly and efficiently again.
This isn’t just a generic part off the shelf. We provide a comprehensive service that ensures this module is a perfect match for your vehicle. Upon purchase, you will provide us with your vehicle’s VIN. Our technicians will then program the ECM with the latest, most stable software updates directly from General Motors. This critical step ensures seamless communication with all other modules in your vehicle, eliminating compatibility issues and ensuring optimal function right out of the box. The result is a simple, plug-and-play installation process that restores factory performance.
From the Diagnostic Bay
We had a 2004 Sierra 2500 come into the shop with a complaint of intermittent stalling and a random P0300 misfire code that mechanics had been chasing for weeks. They had replaced plugs, wires, coils, and even the crankshaft position sensor, but the problem persisted. After hooking up our diagnostic scanner, we noticed the live data for the fuel trims and ignition advance was jumping all over the place with no logical reason. This pointed directly to the processor in the ECM. We installed one of our VIN-programmed 12586242 modules, performed the security relearn, and the truck ran perfectly. The customer saved hundreds, if not thousands, by avoiding further unnecessary parts replacements.
Diagnosing a Faulty 2004 Yukon XL ECM
A failing engine computer can manifest in numerous ways, often mimicking other component failures. If you’re experiencing any combination of the following symptoms, your ECM is a likely culprit. This module is the correct solution for these common issues.
- ✔ Persistent Check Engine Light (CEL) with various codes
- ✔ Engine stalling or shutting off unexpectedly
- ✔ Rough or unstable idling
- ✔ Noticeable decrease in fuel efficiency
- ✔ Hesitation or stumbling during acceleration
- ✔ Harsh or incorrect automatic transmission shifting
- ✔ No-start condition where the engine cranks but won’t fire
- ✔ Communication errors with diagnostic scan tools
Guaranteed Compatibility and Simple Installation
This ECM 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 vehicles such as the Escalade, Avalanche, Sierra, Silverado, Suburban, Tahoe, Hummer H2, Envoy, Trailblazer, and more. By programming it to your specific VIN, we ensure it works perfectly with your vehicle’s engine, transmission, and options package. Installation typically involves disconnecting the battery, unplugging the electrical connectors from the old module, unbolting it, and installing 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
What information do I need to provide for programming?
After you complete your purchase, you will need to send us your vehicle’s 17-digit Vehicle Identification Number (VIN). This is essential for us to load the correct GM-certified software for your specific engine, transmission, and emissions package.
Is this a plug-and-play part?
Yes, because we program the module to your VIN before shipping, it is a plug-and-play installation. In some cases, you may need to perform a security relearn procedure (also known as a CASE learn or anti-theft relearn), which takes about 30 minutes and involves cycling the ignition key. Instructions are readily available online for this simple process.
Where is the ECM located on my 2004 Yukon XL?
On most GM trucks and full-size SUVs from this year, including the Yukon XL, Sierra, and Silverado, the ECM is located in the engine bay on the driver’s side, under the battery tray or next to the airbox.
Will this fix my specific check engine light codes?
This ECM can resolve a wide variety of diagnostic trouble codes (DTCs), especially those related to processor faults, sensor reference voltage, and communication errors. While it can fix codes like P0601, P0606, and others, it’s always best to have a proper diagnosis to confirm the ECM is the root cause of your issue.
Does this unit come with the latest software?
Absolutely. We flash every module with the most current and stable software version available from General Motors for your specific VIN. This helps resolve many known factory issues and improves overall vehicle operation.