Get Your Hard-Working Truck Back on the Job
When your Sierra, Silverado, or Savana van is down, every minute counts. A faulty Engine Control Module (ECM) can bring your entire operation to a halt, causing everything from a no-start condition to unpredictable performance issues that you simply can’t afford. This isn’t just an inconvenience; it’s a hit to your bottom line. We understand that you need a reliable, no-nonsense solution that gets your 6.6L Duramax diesel engine running perfectly again, and this is it.
Common Failure Symptoms & Your Direct Solution
If you’re experiencing any of the following issues, a failing ECM is the likely culprit. This module is the definitive solution for restoring your vehicle’s performance and reliability.
- Complete no-start or intermittent starting problems
- Poor engine performance, reduced power, or erratic idling
- Check Engine Light with Diagnostic Trouble Codes (DTCs) like P0601, P0606, or other internal processor faults
- Loss of communication with the ECM on a scan tool
- Harsh or incorrect transmission shifting
- Unexplained electrical or sensor issues
This programmed 12658036 ECM is engineered to resolve these issues by replacing the faulty brain of your engine with a fully updated and correctly calibrated unit, tailored specifically to your truck.
Features & Benefits
- ✔ VIN-Specific Programming Included: We flash the module with the latest GM software updates using your vehicle’s VIN before it ships. This critical step ensures compatibility and optimal performance, saving you a costly trip to the dealership.
- ✔ Restored Engine Performance: With fresh calibrations, your 6.6L Duramax will regain its proper power, fuel efficiency, and smooth operation.
- ✔ Direct-Fit Guaranteed: This unit is a direct replacement for part numbers 12658036 and 12667377, ensuring a perfect physical fit in the factory location.
- ✔ Built for Dependability: Each module is rigorously inspected to ensure it meets strict quality standards, giving you confidence that your workhorse is ready for any task.
- ✔ This unit is backed by our one-year replacement warranty.
An Expert’s Note on Duramax ECMs
“I’ve seen it countless times: a shop or owner tries to save a few bucks with a used ECM from a salvage yard. For a complex powertrain like the 6.6L Duramax, this is a recipe for disaster. Without the precise VIN-specific programming, you’ll face immobilizer lockouts, incorrect fuel injector flow rates, and transmission compatibility problems. You end up wasting hours of diagnostic time and potentially damaging other components. Getting a pre-programmed 12658036 ECM like this one is the single most effective way to ensure the job is done right the first time, getting you back to work without the headaches.”
Frequently Asked Questions
What information do you need from me after I order?
After you complete your purchase, you must provide us with your vehicle’s 17-digit VIN (Vehicle Identification Number). This is essential for us to program the ECM with the correct software and calibrations for your specific truck or van.
What is a ‘theft deterrent relearn’ and do I have to do it?
Yes. After installation, the vehicle’s anti-theft system needs to recognize the new ECM. This is a standard security procedure called a ‘theft deterrent relearn.’ It must be performed by the installer using a professional GM-compatible scan tool and software like tis2web. The vehicle will not start until this procedure is completed.
Are there any other procedures needed after installation?
Potentially, yes. Depending on your vehicle’s specific configuration, other relearns or setup procedures may be necessary. These can include a crankshaft position variation relearn or setting injector flow rates. These are the responsibility of the installer and are standard practice when replacing an ECM on these models.
Is this a simple plug-and-play part?
It is a direct physical fit and comes electronically prepared for your vehicle. However, due to the mandatory security and system relearn procedures, it is not strictly ‘plug-and-play.’ Professional installation or access to the proper diagnostic tools is required to finalize the installation and start the vehicle.
How do I know if this ECM will fit my vehicle?
This module fits a range of 2014-2015 GM trucks and vans with the 6.6L Duramax Diesel engine, including the Silverado 2500/3500, Sierra 2500/3500, and Express/Savana 2500/3500. Please check the detailed fitment list on this page and verify that your original part number is 12658036 or 12667377 to ensure compatibility.