Restore Your Van’s Core Performance and Reliability
Is your 2016 Chevrolet Express 2500 Van acting up? Experiencing frustrating issues like intermittent stalling, a persistent Check Engine Light, rough idling, or a sudden drop in fuel economy? The Engine Control Module (ECM), the electronic brain of your vehicle, is often the source of these perplexing problems. When it fails, it can disrupt everything from fuel injection to transmission shifting. This isn’t just an inconvenience; it’s a critical failure that compromises your workhorse van’s dependability. This replacement Engine Control Module, part number 12643636, is the definitive solution to restore your vehicle’s factory performance.
We take the guesswork and hassle out of the repair. Unlike sourcing a module from a junkyard or a generic retailer, this unit arrives at your door completely programmed to your specific vehicle. Simply provide us with your van’s Vehicle Identification Number (VIN) after purchase, and our technicians will flash the module with the latest, most stable software updates directly from GM. This means no expensive trips to the dealership for programming, no special tools required for setup, and no compatibility headaches. It’s a direct-fit, plug-and-play solution designed to get your 2016 Express 2500 ECM functioning perfectly again.
Case Study: A Tricky Diagnosis
A few months back, a 2016 Express 2500 work van was towed into my shop. The owner, a local plumber, was at his wit’s end. The van would randomly lose power and stall, but only after it was fully warmed up. He’d already replaced the fuel pump and a couple of sensors with no luck. After connecting my scan tool, I found no communication with the ECM and a tell-tale U0100 code. A physical inspection revealed no wiring damage. In these cases, after verifying power and ground to the module, the culprit is almost always internal failure of the ECM itself, often caused by years of heat cycles and vibration. We installed a VIN-programmed module just like this one, and the van was back in service the same afternoon, running smoother than it had in years. This pre-programmed solution saved my client a tow to the dealer and at least a full day of downtime.
Is Your Vehicle Showing These Symptoms?
- ✔ Check Engine Light is illuminated with codes like P0601, P0606, or U0100 (Lost Communication with ECM/PCM).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained drops in fuel efficiency.
- ✔ The vehicle stalls intermittently, especially when warm.
- ✔ Noticeable hesitation or stumbling during acceleration.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Communication errors with diagnostic scan tools.
A Straightforward Guide to Installation
Replacing the 2016 Express 2500 ECM is a manageable job for a DIYer with basic tools. Follow these steps for a successful installation.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait 10-15 minutes for the system capacitors to discharge before you begin.
- Locate the ECM: On the Express/Savana vans, the ECM is typically located in the engine compartment on the driver’s side, near the firewall or inner fender.
- Disconnect Connectors: Carefully release the locking tabs on the electrical wiring harnesses and pull them straight out from the module. Never force them. Inspect the pins for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. There are usually a few 10mm bolts holding it in place.
- Install the New Module: Mount your new, pre-programmed ECM onto the bracket and secure it with the bolts.
- Reconnect Everything: Firmly plug the wiring harnesses back into the new module until they click into place. Reconnect the negative battery terminal.
- Final Check: Turn the key to the ‘On’ position (without starting the engine) for 10-15 seconds. This allows the other vehicle modules to recognize the new ECM. Then, start your engine. The Check Engine Light should be off, and the vehicle should run smoothly.
Verified Vehicle Compatibility
This module is a direct replacement for part numbers 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200. It is guaranteed to fit the following GM models and engine options. Please verify your part number or contact us with your VIN to ensure compatibility.
- BUICK ENCORE 13-16 (1.4L)
- CADILLAC ELR 14-16
- CHEVROLET CRUZE 12-16 (Gasoline)
- CHEVROLET EXPRESS 2500/3500 VAN 16 (4.8L, 6.0L)
- CHEVROLET SILVERADO 2500/3500 PICKUP 12-16 (6.0L)
- CHEVROLET SONIC 12-16 (1.4L)
- CHEVROLET SPARK 14-15 (Gasoline)
- CHEVROLET SUBURBAN 3500 16
- CHEVROLET TRAX 13-16
- CHEVROLET VOLT 11-15
- GMC SAVANA 2500/3500 VAN 16 (4.8L, 6.0L)
- GMC SIERRA 2500/3500 PICKUP 12-16 (6.0L)
- GMC SIERRA DENALI 2500/3500 12-16 (6.0L)
Frequently Asked Questions About Your 2016 Express 2500 ECM
Do I need to do anything after I install this ECM?
Do I need to do anything after I install this ECM?
No. Because we program the module to your VIN before shipping, it is ready for installation right out of the box. In some cases, a security relearn procedure may be necessary, which can typically be done without special tools. Instructions can be provided if needed.
How do I provide my VIN?
After you complete your purchase, simply send us a message with your 17-digit Vehicle Identification Number (VIN). We cannot program and ship the module without it.
Is this a used part?
This is a fully tested, OEM-quality recycled part. Each module undergoes a rigorous inspection and functional testing process before being programmed with the latest GM software for your vehicle, ensuring reliable performance.
Will this fix my specific problem?
This module will correct issues directly caused by a failing ECM. While the symptoms listed are common indicators of ECM failure, we always recommend a proper diagnosis by a qualified mechanic to confirm the ECM is the root cause before purchasing.