Is Your 2004 GMC Envoy XUV Running Rough?
If your 2004 Envoy XUV is experiencing perplexing issues like stalling, erratic shifting, poor fuel economy, or a persistent Check Engine Light, a failing Powertrain Control Module (PCM) could be the culprit. The PCM is the central brain of your vehicle, managing critical engine and transmission functions. When it starts to fail, it can create a cascade of problems that are often difficult to diagnose. This replacement PCM, part number 12586242, is the definitive solution to restore your vehicle’s performance and reliability.
From the Diagnostic Bay
We once had a 2004 Sierra with the 6.0L come in on a tow truck. The owner had replaced the fuel pump, all the ignition coils, and even the throttle body chasing an intermittent no-start and stalling issue. The codes were all over the place—communication errors, sensor faults, you name it. After hours of diagnostics, we checked the main ground wire for the PCM located on the engine block. It was corroded and loose. After cleaning and tightening it, the truck ran perfectly. While in that case the PCM was fine, a faulty ground can damage the module over time. Always check your main power and ground connections before condemning a PCM, but if they’re good, a faulty module is the next logical step.
Symptoms of a Failing 2004 Envoy XUV PCM
- ✔ Check Engine Light is on with various, often unrelated, trouble codes (DTCs).
- ✔ Engine stalling, stumbling, or misfiring for no apparent reason.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Complete no-start condition where the engine cranks but won’t fire up.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Other modules on the vehicle network acting erratically.
A Plug-and-Play Solution Programmed for Your VIN
Don’t waste time and money at a dealership. This module is not a simple off-the-shelf part. We provide a professionally prepared PCM that is flashed with the latest GM software updates specifically for your vehicle. When you place your order, you’ll need to provide us with your vehicle’s 17-digit Vehicle Identification Number (VIN). Our technicians use this VIN to program the module, ensuring it matches your Envoy XUV’s exact configuration—including engine, transmission, and emissions equipment. This critical step means the computer arrives ready for installation, eliminating the need for expensive dealer programming.
This unit 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 variety of 2004 GM trucks and SUVs like the GMC Sierra, Chevrolet Silverado, Tahoe, Suburban, Escalade, and more. Please verify your service number to ensure compatibility.
Installation Process
Installing your new 2004 Envoy XUV PCM is straightforward for a DIY mechanic. On the Envoy, it’s typically located in the engine bay, next to the air filter box. The process involves disconnecting the vehicle’s battery, carefully unplugging the electrical connectors from the old module, unbolting it from its bracket, and then installing the new one in the reverse order. Once installed and the battery is reconnected, you may need to perform a simple security relearn procedure (often called a CASE relearn), which can be done without special tools and instructions are readily available online.
Frequently Asked Questions
Do I need to have this PCM programmed?
No, we handle the programming for you before shipment. Simply provide your vehicle’s VIN during checkout, and the module will arrive ready to install with the latest GM software updates for your specific vehicle.
Where is the PCM located on my 2004 Envoy XUV?
On the 2004 GMC Envoy XUV with the 5.3L engine, the Powertrain Control Module is located in the engine compartment, mounted in a bracket right next to the air filter housing on the driver’s side.
What happens if I install this without providing a VIN?
The module will not function correctly. It contains generic software and will not be able to communicate with your vehicle’s other systems, likely resulting in a no-start condition and multiple error codes. Programming to your VIN is essential.
Will this fix my transmission shifting problems?
The PCM controls both engine and transmission functions. If your shifting issues are caused by faulty electronic commands from a failing module, then yes, this part is very likely to solve the problem. However, it will not fix internal mechanical issues within the transmission itself.
Is any other procedure required after installation?
In most cases, after installation, you will need to perform a security relearn procedure so the PCM can sync with your vehicle’s anti-theft system. This procedure typically involves a series of key cycles and does not require a special scan tool. You may also need a scan tool for a crankshaft position sensor variation relearn (CASE relearn) to prevent a P1336 trouble code.