2004 Envoy XUV PCM | Pre-Programmed to Your VIN | Part #12586242

End the Guesswork and Get Back on the Road with Confidence

Is your 2004 GMC Envoy XUV running rough, throwing confusing check engine lights, or refusing to start? A failing Powertrain Control Module (PCM) can be the frustrating culprit behind a host of perplexing engine problems. It’s the brain of your vehicle, and when it falters, everything from fuel economy to transmission shifting can suffer. This isn’t just an inconvenience; it’s a matter of reliability and peace of mind. We offer the definitive solution: a replacement PCM, part number 12586242, delivered to your door fully programmed and updated with the latest GM software for your specific vehicle.

Warning Signs and How to Overcome Them

If your vehicle is exhibiting any of these symptoms, a failing PCM could be the cause. Replacing it can restore your vehicle’s health and your driving confidence.

• ✔ Check Engine Light: Persistent illumination, especially with Diagnostic Trouble Codes (DTCs) like P0601, P0602, P0604, or P0606, which point directly to an internal computer fault.
• ✔ Poor Performance: Noticeable loss of power, hesitation during acceleration, or a sudden drop in fuel efficiency.
• ✔ Erratic Shifting: The transmission may shift harshly, unpredictably, or get stuck in one gear.
• ✔ Stalling or No-Start: The engine might stall unexpectedly while driving or fail to start at all, even with a good battery and starter.
• ✔ Communication Issues: Your mechanic’s scan tool may be unable to communicate with the PCM, a clear sign of a critical failure.

Guided Installation for a Smooth Repair

Installing your new 2004 Envoy XUV PCM is a straightforward process you can handle with basic tools. Our goal is to empower you to complete the repair and save on costly shop labor. Follow these steps for a successful installation.

1. Safety First: Begin by disconnecting the negative terminal of your vehicle’s battery to prevent any electrical shorts.
2. Locate the Old PCM: On most GMT360 platform vehicles like the Envoy, Rainier, and Trailblazer, you’ll find the PCM in the engine bay, typically next to the air filter box. On trucks like the Sierra and Silverado, it’s often located on the driver’s side, under the battery tray.
3. Disconnect the Connectors: Carefully release the locking tabs on the wiring harness connectors and gently pull them straight out from the module. Inspect the pins for any corrosion or damage.
4. Swap the Modules: Unbolt the old PCM from its mounting bracket and secure the new one in its place.
5. Reconnect and Power Up: Firmly plug the wiring harnesses into your new, pre-programmed PCM until they click into place. Reconnect the negative battery terminal.
6. Perform Security Relearn: Your vehicle’s anti-theft system may need to be synchronized with the new PCM. This is a simple procedure: Turn the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds. Repeat this cycle two more times. On the fourth try, the vehicle should start, confirming the relearn is complete.

An Expert’s Diagnostic Story

I once had a 2004 Sierra Denali in the bay with a no-start condition that had stumped two other shops. They had replaced the fuel pump and crank sensor to no avail. My scan tool couldn’t even talk to the original computer. Before ordering a new module, I did a quick voltage drop test on the PCM’s main power and ground wires. The ground circuit was perfect, but the power feed was weak. A closer look revealed a corroded wire at the underhood fuse block. After repairing that single wire, the original PCM came back to life. It’s a powerful reminder: always confirm the basics—good power, solid grounds, and a healthy battery—before condemning a computer. This simple check can save you hundreds of dollars and a lot of headaches.

Tailored Fit for Your GM Truck or SUV

This module is a direct replacement for service number 12586242 and is compatible with a wide range of 2004 GM vehicles. We program it specifically to your VIN, ensuring it works seamlessly with your engine, transmission, and factory options. Please verify your part number or one of the compatible service IDs (including YHTN, YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP) for a guaranteed fit.

This part is a confirmed fit for models including:

• 2004 GMC Envoy XL, Envoy XUV, Sierra 1500/2500/3500, Sierra Denali, Yukon, Yukon XL
• 2004 Chevrolet Trailblazer EXT, SSR, Silverado 1500/2500/3500, Suburban 1500/2500, Tahoe, Avalanche 1500
• 2004 Cadillac Escalade, Escalade ESV, Escalade EXT
• 2004 Buick Rainier
• 2004 Hummer H2
• 2004 Isuzu Ascender

By providing your VIN upon purchase, you ensure this replacement 2004 Envoy XUV PCM is a perfect, plug-and-play match, restoring your vehicle to its original factory performance.