Restore Your Truck’s Brain, Restore Your Drive
Is your 2004 Sierra Denali, Silverado, or other GM truck suffering from baffling electrical issues, a persistent check engine light, or poor performance? A failing Powertrain Control Module (PCM) is often the culprit, acting like a broken command center for your engine. This replacement Engine Control Module, service number 12586242, is the definitive solution to get your vehicle running strong again. We take the guesswork out of the repair by programming the unit specifically to your vehicle’s VIN before it ships, ensuring a seamless installation process and restoring the reliable performance you depend on.
Common Symptoms & Your Solution
If you’re experiencing any of the following, a faulty PCM is the likely cause. This pre-programmed module is designed to resolve these exact problems:
- Erratic or rough idling
- Engine stalling or refusing to start
- Poor fuel economy and loss of power
- Check Engine Light (CEL) with communication codes (U-codes)
- Harsh or incorrect automatic transmission shifting
- Apparent failure of multiple unrelated sensors at once
Installing our professionally programmed 2004 Sierra Denali PCM is the most reliable way to fix these issues and get your truck back to factory-spec operation.
Features & Benefits
- โ VIN-Programmed for Your Truck: No need for an expensive trip to the dealer. This module arrives ready to install, pre-flashed with the latest GM software updates for your specific vehicle.
- โ Restored Engine Performance: Eliminates rough idle, hesitation, and stalling by re-establishing precise control over fuel delivery, spark timing, and transmission shifting.
- โ Direct-Fit Replacement: Engineered to replace a wide range of original service numbers, including 12586242, YFKF, YFKD, YFXL, and more, ensuring perfect compatibility.
- โ Clear Your Codes: The correct solution for persistent communication-related Diagnostic Trouble Codes (DTCs) that won’t go away.
- โ Peace of Mind: This unit is backed by our one-year replacement warranty.
An Expert’s Note on Programming:
As a technician, I’ve seen countless DIY repairs go wrong because of an unprogrammed or incorrectly programmed computer. A generic module from a salvage yard won’t workโyour truck’s security system (Passlock/VATS) will prevent it from starting. Our process of programming the module to your specific VIN is not just a convenience; it’s a critical step that integrates the new PCM with your truck’s existing systems, just like the factory intended. This ensures a smooth start-up and avoids a host of frustrating post-installation problems.
Frequently Asked Questions
How does the VIN programming process work?
It’s simple. After you complete your purchase, you will need to provide us with your vehicle’s 17-digit VIN. Our technicians use this number to flash the module with the exact software and calibrations for your truck’s engine, transmission, and options package. This makes the unit ready for installation right out of the box.
Will I need to do anything after installing this PCM?
In most cases, this module is a direct installation. However, some GM vehicles may require a security relearn procedure (often called Passlock or VATS relearn) and a Crankshaft Position Sensor (CASE) relearn. These procedures can typically be performed with a capable bi-directional scan tool and are standard practice for this type of repair.
Is this the correct part for my vehicle?
This module fits a wide range of 2004 GM trucks and SUVs. The best way to confirm is to match the service number on your original computer to 12586242 or one of the other compatible numbers listed in the description. Providing your VIN during checkout allows us to double-check and ensure perfect compatibility.
Where is the PCM located on my 2004 Sierra or Silverado?
On most of the trucks like the Sierra, Silverado, Tahoe, and Suburban, the PCM is located in the engine bay on the driver’s side, under or next to the battery, often mounted to the inner fender.
Do I need to send my old computer back?
No core charge is required for this part. You do not need to return your original, failed module.