Is your 2004 GMC Yukon or other GM truck running rough, stalling, or showing a persistent Check Engine Light?
The Powertrain Control Module (PCM), often called the Engine Control Module (ECM), is the central computer responsible for managing your vehicle’s engine performance, fuel economy, and emissions. When it begins to fail, it can cause a wide range of frustrating and difficult-to-diagnose issues. This replacement PCM, part number 12586242, is the definitive solution to restore your vehicle’s factory performance and reliability.
From the Diagnostic Bay
We had a 2004 Sierra 1500 come in with a complaint of random stalling at stoplights and erratic transmission shifting. The owner had already replaced the throttle body and a few sensors with no luck. After hooking up our diagnostic tools, we noticed intermittent communication loss with the PCM. Instead of guessing, we checked the power and ground circuits to the module, which were solid. This confirmed our suspicion: the internal logic of the original PCM was failing. We installed a VIN-programmed module just like this one, performed the security relearn, and the truck ran perfectly. It’s a classic case where throwing parts at a problem doesn’t work; you need to address the root cause, which is often the vehicle’s main computer.
Symptoms of a Failing 2004 Yukon PCM
If you’re experiencing any of the following issues, a faulty engine computer could be the culprit. A failing PCM can often mimic other component failures, making diagnosis tricky. Look for these common warning signs:
- ✔ Persistent Check Engine Light (CEL) with various trouble codes.
- ✔ Engine stalling or shutting off unexpectedly while driving.
- ✔ Rough or erratic idling.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or incorrect automatic transmission shifting.
- ✔ Complete no-start condition where the engine cranks but won’t fire.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Misfire codes that don’t resolve after replacing plugs, coils, or wires.
The Plug-and-Play Solution for Your GM Vehicle
Don’t settle for a generic, unprogrammed module from a local parts store that requires expensive dealership flashing. We take the guesswork and hassle out of the process. When you order from us, you get a fully prepared module that is ready for installation. Simply provide your vehicle’s 17-digit VIN (Vehicle Identification Number) during or after checkout, and our technicians will flash the unit with the latest, most stable software updates directly from GM. This ensures perfect compatibility and optimal performance for your specific vehicle configuration.
This module is a direct replacement for service number 12586242 and is also compatible with the following service numbers: 19299226, 89017738, YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP, and YHTN. Please verify the part number on your original module to ensure a perfect match.
Installation and Setup
Installation is straightforward for a DIY mechanic or any professional technician. The PCM is typically located in the engine bay, on the driver’s side under the battery tray or next to the airbox. After swapping the physical unit, you may need to perform a simple security relearn procedure, also known as a CASE (Crankshaft Angle Sensor Error) relearn. This procedure allows the new PCM to communicate with your vehicle’s anti-theft system and other modules. This can often be done without special tools and instructions are widely available, or can be completed by any repair shop in minutes.
Frequently Asked Questions
Do I need to have this PCM programmed?
No. We handle the programming for you before we ship the part. Just provide us with your vehicle’s VIN, and it will arrive ready to be installed with the latest GM software updates for your specific vehicle.
Where do I find my vehicle’s VIN?
Your 17-digit VIN can be found on your vehicle’s registration, insurance card, or on the driver’s side of the dashboard, visible through the windshield.
Will this fix my vehicle’s problem for sure?
This PCM will correct any issues directly caused by a faulty engine computer. However, it’s crucial to ensure your vehicle has been properly diagnosed. This part will not fix problems related to other faulty components like sensors, wiring harnesses, or fuel pumps.
Is any special procedure required after installation?
In most cases, you will need to perform a security relearn procedure (also called a CASE relearn). This syncs the new computer with your vehicle’s anti-theft system and crankshaft position sensor. This is a standard procedure that can be performed by most mechanics or knowledgeable DIYers.
How do I confirm this is the exact part I need?
The best way is to match the service number on your current PCM to one of the numbers listed in our description, such as 12586242. Our extensive fitment list also covers many compatible models, but matching the service number is the most accurate method.