Is Your Truck or SUV Running Rough? Get Back on the Road with Confidence.
If you’re dealing with a frustrating check engine light, erratic shifting, poor fuel economy, or a no-start condition in your 2004 GM vehicle, a failing Powertrain Control Module (PCM) is often the culprit. Don’t let a faulty computer keep your reliable workhorse parked. This is the definitive, plug-and-play solution to restore your vehicle’s performance and get you back to driving with peace of mind. We provide a professionally programmed PCM, flashed with the latest GM software updates specifically for your vehicle’s VIN, making installation straightforward and eliminating the need for an expensive trip to the dealership.
Common Symptoms & Your Solution
A failing engine computer can cause a wide range of issues that can be difficult to diagnose. If you’re experiencing any of the following, this module is your solution:
- Persistent Check Engine Light (CEL)
- Diagnostic Trouble Codes (DTCs) like P0601, P0602, P0606, or other communication errors
- Vehicle won’t start or has intermittent starting problems
- Poor engine performance, hesitation, or stalling
- Decreased fuel mileage
- Harsh or incorrect transmission shifting
This professionally programmed 2004 Sierra Denali 12586242 PCM is engineered to resolve these issues, restoring the factory performance and communication your vehicle’s complex systems rely on.
Features & Benefits: The Right Part, Programmed Correctly
- ✔ VIN-Programmed for Your Vehicle: We flash the unit with your truck’s specific VIN and the latest GM calibrations before it ships. This ensures compatibility and proper function right out of the box.
- ✔ Latest GM Software Updates: Your module arrives with the newest software from General Motors, addressing known bugs and optimizing engine and transmission performance for maximum reliability.
- ✔ Direct OEM Replacement: This is a genuine OEM unit, guaranteeing a perfect fit and seamless integration with your vehicle’s existing wiring and mounting locations. This unit is a direct replacement for service numbers 12586242, 19299226, 89017738, and many more.
- ✔ Cost-Effective Dealership Alternative: Skip the high costs and scheduling hassles of the dealership service department. This is a simple, direct solution for both experienced DIY mechanics and professional repair shops.
- ✔ Backed by Our Warranty: This unit is backed by our one-year replacement warranty. Drive with the assurance that your purchase is protected.
Expert Insight: Why a Programmed Module is Non-Negotiable
As a veteran technician, I’ve seen countless vehicle owners try to save a few dollars by installing a used, non-programmed computer from a salvage yard. This almost never ends well. The PCM in your 2004 GM truck is not just a simple box; it’s the brain, containing the VIN, security information (Passlock/VATS), and specific operating parameters for your engine, transmission, and options package. Installing an incorrect or non-programmed module will, at best, result in a no-start condition and, at worst, can damage other electronic components. Our service takes the guesswork and risk out of the repair. We handle the critical programming, so you receive a part that is truly ready to be installed in your vehicle.
Ordering is simple. After you complete your purchase, just provide us with your vehicle’s VIN. We’ll handle the programming and ship your ready-to-install 2004 Sierra Denali 12586242 PCM directly to you. It’s the most reliable way to fix your truck and get back to what matters.
Frequently Asked Questions
Do I need to do anything after installing the PCM?
In most cases, you will need to perform a security relearn procedure (often called a VATS relearn). This process is simple, requires no special tools, and typically involves a sequence of turning the key on and off. We include instructions to guide you through this 10-30 minute procedure.
How do I provide my VIN?
You can add your 17-digit Vehicle Identification Number (VIN) to the notes section during checkout. If you forget, don’t worry—we will contact you via email after your purchase to request it. We cannot ship your part until we have your VIN.
Will this fix my specific problem?
This module is a guaranteed fix for any issue directly caused by a faulty internal PCM circuit. While it resolves the vast majority of electronic engine and transmission issues, it’s important to ensure your vehicle’s wiring, sensors, and other mechanical components are in good working order. Proper diagnosis is key.
Is this a brand new part?
This is a high-quality, genuine OEM unit that has been thoroughly tested and programmed to function to original factory specifications. It provides the same reliability and performance as a module from the dealership at a fraction of the cost.
My original part number is different. Will this still work?
Yes. GM often updates part numbers over time. This module, part number 12586242, is the correct, updated replacement for a long list of earlier service numbers, including YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP, and YHTN. Please check the fitment list to confirm for your vehicle.
What is the complete fitment for this 2004 Sierra Denali 12586242 PCM?
This computer fits a wide range of 2004 GM models including the Avalanche, Escalade (ESV, EXT), Sierra/Silverado (1500, 2500, 3500), Suburban, Tahoe, Yukon, Hummer H2, SSR, Envoy (XL, XUV), Trailblazer EXT, Rainier, and Isuzu Ascender. Please verify the specific service ID for your vehicle against our compatibility list.