Restore Your Vehicle’s Brain and Get Back on the Road
As a technician with over two decades of experience under the hood, I’ve seen firsthand the chaos a failing Engine Control Module (ECM) can cause. It’s the central computer of your vehicle, and when it starts to falter, you can experience everything from a simple check engine light to a frustrating no-start condition. If your 2016 Suburban 3500 is acting up, this replacement ECM is the reliable, straightforward solution you need. This isn’t just a part in a box; it’s a complete service. We flash the module with the latest GM-certified software specific to your vehicle’s VIN, ensuring it’s ready for installation the moment it arrives. This process eliminates the need for an expensive trip to the dealership for programming, saving you both time and money.
The ECM is responsible for managing critical functions like fuel mixture, ignition timing, and transmission shifting. A faulty one can lead to poor performance, abysmal fuel economy, and failed emissions tests. This replacement module is meticulously tested to restore your vehicle’s original functionality and efficiency. By providing us with your VIN at checkout, you ensure that the 2016 Suburban 3500 Engine Control Module you receive is a perfect match for your vehicle’s specific configuration.
Case Study: A Tricky Diagnosis
A customer brought in a 2016 Silverado 2500 (which uses the same ECM as the Suburban 3500) with a complaint of intermittent stalling and a flurry of communication error codes (U0100, U0101). We checked all the basics—power, grounds, and the CAN bus network wiring—and everything looked solid. The symptoms pointed directly to an internal failure of the ECM. After swapping in a pre-programmed module just like this one, all the communication codes vanished, and the truck ran perfectly. It’s a classic example of how a failing ECM can mimic other problems, and why a quality, correctly programmed replacement is the definitive fix.
Is Your Vehicle Showing These Symptoms?
- ✔ Check Engine Light is illuminated with codes like P0601, P0606, or other internal processor faults.
- ✔ The engine cranks but refuses to start.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ The engine runs rough, misfires, or stalls unexpectedly.
- ✔ Automatic transmission shifts harshly or at the wrong times.
- ✔ Loss of communication with the module when using a scan tool.
- ✔ Failure to pass state emissions testing.
A Straightforward Guide to Installation
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post.
- ✔ Locate the ECM: On the 2016 Suburban 3500, the ECM is typically found in the left-hand (driver’s side) front of the engine compartment.
- ✔ Disconnect Harnesses: Carefully release the locking tabs on the electrical connectors and pull them straight out from the module. Do not force them.
- ✔ Remove the Old Module: Unbolt the mounting hardware that secures the old ECM to its bracket.
- ✔ Install the New Module: Mount your new, pre-programmed 2016 Suburban 3500 Engine Control Module in place and secure it with the original hardware.
- ✔ Reconnect Everything: Firmly plug the electrical harnesses back into the new ECM until they click into place. Reconnect the negative battery terminal.
- ✔ Final Steps: In some cases, a security relearn procedure may be required. This can often be done without special tools by cycling the key. Consult your vehicle’s service information for specific steps.
Verified Vehicle Compatibility
This ECM, part number 12668866, is a direct replacement for a wide range of GM vehicles. While this listing is for a 2016 Suburban 3500 Engine Control Module, it also fits the models listed below. It is a replacement for part numbers 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200.
CHEVROLET SONIC 2012-2016 (1.4L)
CADILLAC ELR 2014-2016
CHEVROLET EXPRESS 2500/3500 VAN 2016 (4.8L, 6.0L)
GMC SAVANA 2500/3500 VAN 2016 (4.8L, 6.0L)
CHEVROLET SILVERADO 2500/3500 PICKUP 2012-2016 (6.0L)
GMC SIERRA 2500/3500 PICKUP 2012-2016 (6.0L)
GMC SIERRA DENALI 2500/3500 2012-2016 (6.0L)
CHEVROLET VOLT 2011-2015
CHEVROLET TRAX 2013-2016
CHEVROLET SPARK 2014-2015 (Gasoline)
BUICK ENCORE 2013-2016 (1.4L)
CHEVROLET SUBURBAN 3500 2016
Frequently Asked Questions
Do I need to do anything after I purchase?
Yes. After your purchase, you must send us your vehicle’s 17-digit VIN. We cannot program and ship your module without it. This ensures the software is perfectly matched to your vehicle’s factory specifications.
Is this part difficult to install?
For most DIYers with basic tools, this is a straightforward replacement. The module is typically easy to access in the engine bay. The most important part is that our programming service means you won’t need advanced scan tools for software installation.
Will I need to perform a security relearn procedure?
On many GM vehicles, a security relearn (also known as a Passlock or Passkey relearn) is necessary to allow the vehicle to start. This procedure typically involves cycling the ignition key and can be done in your driveway without special tools. We recommend searching for the specific procedure for your model year.
What if the part number on my old module is different?
This module replaces several different GM part numbers, including 12668994, 12643636, and others listed above. As long as your vehicle is on the compatibility list, this module will function correctly once programmed to your VIN.
What is the warranty on this module?
This part comes with our standard warranty, guaranteeing it to be free from defects in materials and workmanship. Please see our warranty page for full details and terms.