Bring Your GM Truck or SUV Back to Life
Is your ride suffering from a persistent check engine light, erratic shifting, or a frustrating no-start condition? These aren’t just annoyances; they’re signs that the very brain of your vehicle, the Powertrain Control Module (PCM), may be failing. This isn’t just a part—it’s the key to restoring the smooth, reliable performance you depend on. We offer a direct-fit, professionally programmed PCM, part number 12586242, that arrives ready to install, getting you back on the road with confidence and peace of mind.
Warning Signs and How to Overcome Them
A faulty PCM can create a cascade of confusing problems. This module is your definitive solution if you’re experiencing:
- ✔ Persistent Check Engine Light (CEL)
- ✔ Diagnostic Trouble Codes (DTCs) like P0601, P0602, P0606, or other internal processor faults
- ✔ Unexplained drops in fuel economy
- ✔ Harsh or unpredictable automatic transmission shifting
- ✔ Engine stalling, stumbling, or rough idling
- ✔ Complete failure to start, even with a good battery and starter
An Expert’s Note: The End of a Diagnostic Dead End
“I once worked with a customer who had spent months and hundreds of dollars chasing a mysterious intermittent stalling issue on his 2004 Sierra. He’d replaced sensors, checked wiring, and was at his wit’s end. The problem was, the old PCM wasn’t throwing a clear code—it was just slowly failing. Once we installed a properly programmed module, it was like a new truck. It’s a powerful reminder that sometimes, the most complex problems have a straightforward solution. This isn’t just about replacing a part; it’s about reclaiming your vehicle’s dependability.”
Guided Installation to Restore Peace of Mind
We’ve made this repair as simple as possible. Because we program the module to your vehicle’s specific Vehicle Identification Number (VIN) before it ships, you get the latest GM software updates without needing a trip to the dealership. Follow these steps for a successful installation:
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the Old Module: On most compatible vehicles like the Envoy, Trailblazer, and Rainier, you’ll find the PCM in the engine bay, next to the air filter box. On trucks like the Silverado and Sierra, it’s typically located on the driver’s side, under the battery tray.
- Swap the Connectors: Carefully unclip the wiring harnesses from the old PCM. They are color-coded and keyed, so they can only go back on one way. Remove any bolts securing the old module.
- Install the New PCM: Mount your new, pre-programmed PCM in place and securely reconnect the wiring harnesses. You should hear a confident ‘click’ as they lock in.
- Reconnect and Start: Reattach the negative battery terminal. In some cases, a security relearn procedure may be necessary, which typically involves turning the key to the ‘ON’ position for 10-15 minutes. Start the engine and enjoy the restored performance.
The Advantage of a Programmed 2004 Envoy XUV PCM
Ordering a pre-programmed module saves you significant time, money, and hassle. There’s no need for expensive dealership programming or specialized scan tools. We handle the complex part, loading the correct software and updates for your specific VIN. This ensures all systems, from the engine timing to the transmission shift points, operate exactly as the manufacturer intended.
Tailored Fit for Your Ride
This module is the correct replacement for service numbers 12586242, 19299226, 89017738 and broadcast codes including YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP, YHTN. It is guaranteed to fit a wide range of 2004 GM models, including:
- Buick Rainier (5.3L)
- Cadillac Escalade, ESV, EXT
- Chevrolet Avalanche 1500, SSR, Silverado 1500/2500/3500, Suburban 1500/2500, Tahoe, Trailblazer EXT (5.3L)
- GMC Envoy XL/XUV (5.3L), Sierra 1500/2500/3500, Sierra Denali, Yukon, Yukon XL 1500/2500
- Hummer H2
- Isuzu Ascender (5.3L)
After purchasing, please provide your VIN to ensure we can program the module for a perfect, plug-and-play fit.
Frequently Asked Questions
Do I need to get this computer programmed?
No. We handle all the programming for you before we ship the part. Simply provide us with your vehicle’s VIN during checkout, and it will arrive ready for installation with the latest software from GM.
Where is the PCM located on my 2004 GM vehicle?
The location varies slightly by model. On SUVs like the Envoy, Trailblazer, and Rainier, it’s typically found in the engine compartment next to the air filter box. On full-size trucks like the Silverado and Sierra, it’s usually on the driver’s side of the engine bay, underneath the battery tray.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the PCM (common codes include P0601 through P0606), then yes, this part is the correct solution. However, a check engine light can be triggered by many other components, so proper diagnosis is always recommended.
My original part has a different service number. Will this still work?
Yes. This module, part number 12586242, is the correct replacement for a wide range of service numbers and broadcast codes listed in the description. As long as your vehicle is on the compatibility list, we will program this module to function perfectly for your specific application.
Is a security or CASE relearn required after installation?
In most cases, the vehicle will start and run immediately. Some GM vehicles may require a simple security relearn procedure, which can be done without any special tools. This usually involves cycling the ignition key and waiting for 10-15 minutes. A CASE (Crankshaft Position System Variation) relearn may be needed to clear a P1336 code, which requires a capable scan tool, but the vehicle will still be drivable without it.