Restore Peak Performance to Your GM Truck or Van
As a technician with over two decades of experience under the hood, I’ve seen firsthand the headaches a failing Engine Control Module (ECM) can cause. Your 2012-2016 Sierra 3500 Pickup is a workhorse, but when its electronic brain starts to falter, you get frustrating symptoms like a persistent Check Engine Light, poor fuel economy, erratic shifting, or even a no-start condition that leaves you stranded. This isn’t just an inconvenience; it’s a critical failure that compromises your vehicle’s reliability and performance. This module is the definitive solution, arriving pre-programmed with the latest GM software specifically for your vehicle’s VIN.
Forget the hassle and expense of towing your truck to a dealership for programming. We handle the critical software flashing process for you before the part ever leaves our facility. All you need to do is provide your vehicle’s VIN during checkout, and we’ll ensure this replacement Sierra 3500 Engine Module is ready for installation right out of the box. This streamlines the repair process, saving you significant time and money, whether you’re a professional mechanic aiming for bay efficiency or a DIYer tackling the job in your own garage.
From the Diagnostic Bay: The Intermittent Stall Case
I remember a 2014 Sierra 2500 with the 6.0L that came into my shop with a maddening intermittent stalling issue. No codes, no warning lights—it would just die at a stoplight and then fire right back up. The owner had already replaced the fuel pump and crank sensor. We spent hours checking wiring harnesses and grounds, finding nothing. On a hunch, I monitored the ECM’s internal voltage and temperature PIDs on my scan tool. I noticed the voltage would dip erratically just before a stall. We swapped in a known-good ECM, and the problem vanished. The original module had an internal power regulation fault that only appeared under specific conditions. This case highlights how a faulty Sierra 3500 Engine Module can create ghost-in-the-machine problems that defy typical diagnostics.
Is Your Truck’s ECM Failing? Watch for These Signs
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, it’s a strong indicator that the brain of your engine needs attention. Often, these symptoms are accompanied by specific Diagnostic Trouble Codes (DTCs).
- ✔ Persistent Check Engine Light (CEL) that won’t clear.
- ✔ Engine stalling, misfiring, or running rough.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Transmission shifting issues or harsh engagement.
- ✔ Complete no-start or intermittent starting problems.
- ✔ Communication error codes, such as U0100 (Lost Communication With ECM).
- ✔ Internal module failure codes, like P0601, P0606, or P062F.
A Straightforward Guide to Installation
Replacing your Sierra 3500 Engine Module is a manageable job for someone with moderate mechanical skill. Following these steps will ensure a smooth process. Note: A security relearn procedure may be required after installation, which can typically be done without special tools.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the ECM: On most 2012-2016 Sierra/Silverado trucks, the ECM is located in the engine compartment on the driver’s side, near the firewall or inner fender.
- Disconnect Connectors: Carefully release the locking tabs and disconnect all electrical wiring harness connectors from the old module. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the mounting hardware that secures the ECM to its bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed ECM in the same location and secure it with the original hardware.
- Reconnect Everything: Firmly plug the wiring harness connectors into the new module until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn: Turn the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds. Repeat this cycle three times. This often completes the vehicle’s anti-theft relearn process. Start the engine to verify the repair.
Verified Vehicle Compatibility
This Engine Control Module is a direct-fit replacement for a wide range of General Motors vehicles. It is compatible with units bearing part numbers 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200. Please verify your part number or contact us with your VIN to confirm compatibility for the following models:
- Buick Encore: 2013-2016 (1.4L)
- Cadillac ELR: 2014-2016
- Chevrolet Cruze: 2012-2016 (Gasoline)
- Chevrolet Express 2500/3500 Van: 2016 (4.8L, 6.0L)
- Chevrolet Silverado 2500/3500 Pickup: 2012-2016 (6.0L)
- Chevrolet Sonic: 2012-2016
- Chevrolet Spark: 2014-2015 (Gasoline)
- Chevrolet Suburban 3500: 2016
- Chevrolet Trax: 2013-2016
- Chevrolet Volt: 2011-2015
- GMC Savana 2500/3500 Van: 2016 (4.8L, 6.0L)
- GMC Sierra 2500/3500 Pickup & Denali: 2012-2016 (6.0L)
Frequently Asked Questions
Why do I need to provide my VIN?
Your Vehicle Identification Number (VIN) is essential for us to program the module with the exact software and calibrations specific to your truck’s engine, transmission, and options. This ensures seamless communication and proper function.
Is this a simple plug-and-play part?
Because we pre-program it to your VIN, it’s as close to plug-and-play as possible. However, as with most ECM replacements on GM vehicles, you will likely need to perform a security/anti-theft relearn procedure, which is a simple process that does not require special tools.
Will this fix my Check Engine Light?
If the Check Engine Light is caused by an internal failure of your existing ECM (e.g., codes P0601, P0606), this part is the correct fix. It’s crucial to properly diagnose the issue first to ensure the ECM is the root cause.
Are there any other part numbers this module replaces?
Yes, this unit is a direct replacement for several part numbers, including 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200, among others listed in our compatibility chart.
What is the warranty on this part?
This module comes with our standard warranty, ensuring it is free from defects in material and workmanship. Please see our warranty page for full details and terms.