Restore Peak Performance to Your GM Truck or SUV
Is your 2004 Trailblazer EXT, Sierra, or Tahoe running rough, stalling, or refusing to start? A failing Powertrain Control Module (PCM) is often the culprit behind these frustrating and unpredictable issues. This isn’t just an inconvenience; it’s a critical failure that compromises your vehicle’s performance, fuel economy, and reliability. Get back behind the wheel with confidence with this direct-replacement, VIN-programmed engine computer, designed to restore your vehicle’s factory performance and get you back on the road without a costly trip to the dealership.
Common Symptoms & Your Solution
If you’re experiencing any of the following, a faulty ECM is the likely cause. This module is the definitive solution for issues such as:
- Persistent Check Engine Light (CEL)
- Engine stalling or cutting out unexpectedly
- Rough idling or misfires
- Poor fuel mileage
- Erratic or failed automatic transmission shifting
- Complete no-start condition
- Communication error codes (e.g., U0100)
Our pre-programmed 2004 Trailblazer EXT PCM 12586242 is engineered to solve these problems by restoring the critical link between your engine’s sensors and its core operating systems.
Features & Benefits
- ✔ Plug & Play Installation: This computer arrives programmed to your vehicle’s specific VIN. No expensive dealer flashing required.
- ✔ Latest GM Software: We flash each module with the newest updates from General Motors, ensuring optimal efficiency, emissions, and performance.
- ✔ Guaranteed Compatibility: A perfect match for service numbers 12586242, 19299226, 89017738, and many others. See our full fitment list.
- ✔ Restored Drivability: Eliminate stalling, hesitation, and rough running to make your vehicle dependable again.
- ✔ Cost-Effective Solution: Get the correct, ready-to-install part and avoid the high labor costs and markups of a repair shop or dealership.
- ✔ Peace of Mind Protection: This unit is backed by our one-year replacement warranty.
Expert Insight: The Critical Role of VIN Programming
Many people assume you can just swap a computer from a junkyard vehicle. On these 2004 GM models, that’s a recipe for failure. The PCM is tied directly to your vehicle’s specific options and, most importantly, the anti-theft system (VATS/Passlock). Without programming it to your exact VIN, the vehicle simply won’t start. Our process ensures the computer communicates perfectly with all other modules in your truck, making the installation process as simple as swapping the part and turning the key.
Frequently Asked Questions
Do I need to do any additional programming?
No. This 2004 Trailblazer EXT PCM 12586242 comes fully programmed to the VIN you provide during checkout. It is ready for installation right out of the box. In some rare cases, a security relearn procedure may be necessary, which is a simple process you can do yourself.
What information do you need from me?
After you complete your purchase, we will need your vehicle’s 17-digit Vehicle Identification Number (VIN). This allows us to load the correct, updated software for your specific engine, transmission, and options.
How do I find my original part number?
Your original part’s service number is printed on a white sticker on the case of the computer itself. It will match one of the numbers listed, such as 12586242, YFKD, YFKF, or others in our compatibility list.
Will this fix my transmission shifting problems?
In many GM vehicles, the PCM also controls transmission functions. If your shifting issues are caused by faulty computer logic or sensor readings, this replacement module will correct the problem. However, it will not fix internal mechanical failures within the transmission.
Is this a brand new part?
This is a high-quality, professionally tested replacement part that has been verified to meet or exceed original equipment specifications. Each unit is inspected and programmed by our expert technicians.
What is the warranty on this computer?
This unit is backed by our one-year replacement warranty, giving you confidence in your repair.