Is Your 2004 GM Truck or SUV Experiencing Engine Problems?
If your 2004 GMC Envoy XUV, Chevrolet Trailblazer, Silverado, or another compatible GM vehicle is suffering from erratic behavior, poor fuel economy, 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 wide range of frustrating and potentially damaging issues, leaving you stranded and facing a costly repair bill from the dealership.
From the Diagnostic Bay
We had a 2004 Trailblazer EXT with the 5.3L come into the shop with a bizarre complaint. The owner said it would randomly stall at stoplights, but only after it was fully warmed up. There were no consistent trouble codes, just a random misfire code that would pop up now and then. We checked fuel pressure, scanned for vacuum leaks, and tested the ignition system—everything looked perfect. On a hunch, we monitored the live data from the PCM and noticed the injector pulse width would suddenly drop to zero right before it stalled. After swapping in a known-good PCM, the problem vanished. It was a classic case of internal PCM failure that only showed up under specific temperature conditions, a common issue with these units.
Symptoms of a Failing PCM
- ✔ Check Engine Light is on with various communication or sensor codes.
- ✔ Vehicle refuses to start or has difficulty starting.
- ✔ Rough idling, stalling, or hesitation during acceleration.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Transmission shifting issues, such as harsh shifts or getting stuck in gear.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Apparent failure of multiple unrelated sensors at the same time.
The Direct-Fit Solution: A Programmed 2004 Envoy XUV PCM
Don’t let a faulty engine computer keep your truck off the road. This replacement PCM, service number 12586242, is the definitive solution to restore your vehicle’s performance and reliability. We take the hassle and high cost out of the equation. Unlike a generic module from a parts store, each unit is professionally programmed with the latest GM software updates specifically for your vehicle. All we need is your Vehicle Identification Number (VIN) at the time of purchase. This ensures that when the part arrives, it’s ready for a straightforward installation.
This module is a direct replacement for a wide range of 2004 GM trucks and SUVs, eliminating the need for expensive dealership programming. By providing your VIN, you guarantee that the fuel maps, transmission shift points, and all other critical operating parameters are perfectly matched to your vehicle’s original specifications.
Simple Installation Process
Once you receive your pre-programmed module, the final step is a simple security relearn procedure, also known as a CASE (Crankshaft Angle Sensor Error) relearn. This can often be performed without any special tools and is necessary to sync the new PCM with your vehicle’s anti-theft system. Instructions for this procedure are readily available online or in service manuals for your specific model.
Guaranteed Fitment
This PCM is a direct replacement for service numbers 12586242, 19299226, 89017738, YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP, and YHTN. It fits a wide variety of 2004 models, including:
- GMC Envoy XL, Envoy XUV, Sierra 1500/2500/3500, Sierra Denali, Yukon, Yukon XL
- Chevrolet Avalanche 1500, Silverado 1500/2500/3500, SSR, Suburban 1500/2500, Tahoe, Trailblazer EXT
- Cadillac Escalade, Escalade ESV, Escalade EXT
- Buick Rainier
- Hummer H2
- Isuzu Ascender
Please verify the service number on your current module to ensure an exact match. If you are unsure, contact us with your VIN, and we will confirm compatibility for your 2004 Envoy XUV PCM or other GM model.
Frequently Asked Questions
Do I need to send my old PCM in?
No core charge or return is required for this part. You can keep your old module.
What is VIN programming?
VIN programming involves loading your vehicle’s specific software and calibrations onto the PCM. This ensures the computer works seamlessly with your engine, transmission, and options package, just as it did from the factory.
Is this a plug-and-play part?
Almost. It comes fully programmed to your VIN, so no dealership visit is needed. However, you will need to perform a security relearn procedure after installation, which syncs the new computer to your vehicle’s anti-theft system. This procedure typically takes 10-30 minutes and can be done at home.
Where do I find my vehicle’s VIN?
Your 17-digit VIN can be found on your vehicle’s registration, insurance card, or on a placard on the driver’s side dashboard visible through the windshield.
Will this fix my specific problem?
This PCM will correct issues directly caused by a faulty engine computer. While the symptoms listed are common indicators of PCM failure, we always recommend a proper diagnosis by a qualified mechanic to confirm the PCM is the root cause of your vehicle’s problems before ordering.