Restore Peak Performance to Your GM Truck or SUV
Is your 2004 GMC Yukon XL 1500, or another compatible GM vehicle, suffering from perplexing issues like stalling, rough idling, poor fuel economy, or a persistent check engine light? The Powertrain Control Module (PCM), often called the engine computer, is the electronic brain responsible for managing your engine’s performance, fuel delivery, ignition timing, and transmission shifting. When it begins to fail, it can cause a cascade of frustrating and difficult-to-diagnose problems. This replacement PCM, service number 12586242, is the definitive solution to restore your vehicle’s factory performance and reliability.
From the Diagnostic Bay
I remember a 2004 Silverado that came in on a tow truck. The owner was at his wit’s end. It would start and run fine for days, then suddenly refuse to start, with no spark and no fuel injector pulse. He had already replaced the crank sensor and fuel pump. After confirming all power and grounds to the PCM were good, we connected our diagnostic tools and found the module would intermittently drop communication. We swapped in a pre-programmed PCM just like this one, performed the quick security relearn, and the truck fired up instantly. It’s a classic case where the central computer was the culprit, and a reliable, correctly programmed replacement was the only true fix.
Common Symptoms of a Failing GM PCM
- ✔ Persistent Check Engine Light (CEL) with various communication or sensor codes.
- ✔ Engine stalling, stumbling, or misfiring, especially under load.
- ✔ Complete no-start condition where the engine cranks but won’t fire up.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Failure to pass state emissions testing.
- ✔ Inconsistent instrument panel warnings or gauge behavior.
Why Choose Our Programmed 2004 Yukon XL PCM?
Getting your vehicle back on the road shouldn’t be a hassle. Unlike a generic module from a parts store or salvage yard, this PCM is delivered to you ready for installation. We take your vehicle’s unique Vehicle Identification Number (VIN) at the time of purchase and flash the module with the latest, most stable software updates directly from General Motors. This critical step ensures that the computer is perfectly matched to your vehicle’s specific engine, transmission, and options, eliminating compatibility conflicts and the need for expensive dealership programming.
This unit is a direct replacement for a wide range of service numbers, including 12586242, 19299226, 89017738, and broadcast codes such as YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP, and YHTN. It is engineered to fit a vast array of 2004 GM models, including the Sierra, Silverado, Tahoe, Suburban, Escalade, Envoy, Trailblazer, Rainier, and more. Please verify your service number or check the comprehensive fitment list to confirm compatibility.
Frequently Asked Questions
Do I need to get this PCM programmed by a dealer?
No. We program the module to your vehicle’s specific VIN before shipping it to you. It arrives ready for installation, saving you a trip to the dealership and additional programming fees.
What is the security relearn procedure?
After installation, you will need to perform a simple security relearn, also known as a Passlock relearn. This procedure syncs the new PCM with your vehicle’s anti-theft system. It typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. Specific instructions are readily available online for your model.
Where is the PCM located on my 2004 GM truck or SUV?
On most full-size trucks and 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 mid-size SUVs like the Trailblazer and Envoy, it is typically found next to the air filter box.
Why do you need my VIN?
The Vehicle Identification Number (VIN) is a unique 17-digit code for your vehicle. It allows us to load the exact factory software and calibrations for your specific engine size, transmission type, and other options, ensuring perfect compatibility and performance.
Will this computer fix my transmission shifting problems?
In many cases, yes. The PCM controls the electronic solenoids that manage shifting in the automatic transmission. If the PCM is faulty, it can cause hard shifts, delayed shifting, or slipping between gears. Replacing a bad PCM often resolves these issues.