Is Your 6.6L Duramax Acting Up? Get Back on the Road Fast.
If your 2013-2014 GM truck or van is experiencing perplexing issues like a no-start condition, erratic engine behavior, or a dashboard full of warning lights, a failing Engine Control Module (ECM) is a very likely culprit. As the central computer for your 6.6L Duramax engine, its proper function is non-negotiable. This isn’t just an inconvenience; for a workhorse vehicle like a Savana or Sierra, it’s a direct hit to your productivity and livelihood. We offer a dependable and straightforward solution: a genuine, used GM ECM, part number 12654088, fully programmed to your vehicle’s specific VIN.
Common Symptoms of a Failing GM 6.6L ECM:
Over my 20+ years in diagnostics, I’ve seen hundreds of these Duramax-powered vehicles roll into the shop. The symptoms of a bad ECM can often mimic other problems, but here are the classic signs I look for:
- โ Complete no-start or intermittent starting problems.
- โ Engine stalling unexpectedly while driving.
- โ Poor fuel economy and noticeable loss of power.
- โ Check Engine Light is on with communication-related fault codes (U-codes).
- โ Issues with the transmission shifting incorrectly, as the ECM communicates directly with the TCM.
- โ Injector or glow plug circuit fault codes that won’t clear even after replacing the parts.
Expert Pro Tip: Check Your Connectors First!
Before you even think about installing a replacement module, take a bright flashlight and carefully inspect the pins on the vehicle’s wiring harness connectors that plug into the ECM. I’ve seen cases where a single corroded or bent pin was the real source of the problem, not the module itself. Cleaning the connectors with a dedicated electronics cleaner and ensuring all pins are straight can save you a massive headache and confirm the ECM is truly the part that needs replacing.
Why Choose Our Programmed 2013-2014 Savana 3500 ECM?
This isn’t just a used part pulled from a yard. We take a quality, road-tested ECM and professionally flash it with the latest official GM software calibrations for your exact vehicle. Simply provide us with your 17-digit Vehicle Identification Number (VIN) during checkout, and we handle the programming before it ships. This critical step ensures the module communicates correctly with the other systems in your truck or van, restoring factory performance and functionality.
Important: Post-Installation Procedures Are Required
To ensure a successful repair, please be aware of the following. This is standard procedure for replacing a modern ECM and is the responsibility of the installer.
- Vehicle Anti-Theft System (VATS/Passlock) Relearn: After installation, your vehicle’s security system will not recognize the new ECM, and it will likely not start. A security relearn procedure must be performed. This typically requires a professional scan tool or access to GM’s TIS2Web service.
- Other System Relearns: Depending on your vehicle’s specific configuration, additional procedures may be necessary. These can include a Crankshaft Position Variation Relearn (CASE relearn), injector flow rate programming, and other setups to ensure all engine parameters are perfectly synchronized.
Guaranteed Fitment for Your GM 6.6L Duramax
This ECM is a direct replacement for part number 12654088 and service number 12653319. It is confirmed to fit the following vehicles equipped with the 6.6L diesel engine:
- 2013-2014 Chevrolet Silverado 2500 / 3500 (incl. Denali)
- 2013-2014 GMC Sierra 2500 / 3500 (incl. Denali)
- 2013-2014 Chevrolet Express 2500 / 3500 Van
- 2013-2014 GMC Savana 2500 / 3500 Van
Please note for 2014 Express/Savana models: This fits standard models, not those with the ‘pull-ahead design’ option.