Restore Your Van’s Performance and Reliability
Is your 2016 Savana 3500 van running rough, stalling unexpectedly, or showing a persistent check engine light? These are classic signs of a failing Engine Control Module (ECM), the central computer of your vehicle. A faulty ECM can cause a cascade of frustrating issues, from poor fuel economy to a no-start condition that leaves you stranded. This isn’t just an inconvenience; for a work vehicle like the Savana, downtime means lost money. This replacement ECM, part number 12643636, is the definitive solution to get your vehicle operating precisely as it should.
What sets this module apart is our professional programming service. Before we ship it, we flash the module with the latest GM-certified software, tailored specifically to your vehicle’s Vehicle Identification Number (VIN). This means it arrives at your door ready for a straightforward installation, saving you the time, cost, and hassle of a trip to the dealership for programming. It’s a direct-fit, plug-and-play solution designed for reliability.
A Technician’s Notebook: The Intermittent Gremlin
I remember a 2016 Express 3500—the Savana’s twin—that came into my shop with a problem that was driving the owner crazy. It would run perfectly for days, then suddenly start stumbling, lose power, and throw a U0100 (Lost Communication with ECM/PCM) code, only for the issue to vanish after a restart. We checked wiring harnesses, grounds, and power feeds, but everything tested fine. After hours of diagnostics, we suspected the ECM itself was failing internally, likely due to heat cycles causing a hairline crack in a solder joint. We swapped in a VIN-programmed ECM just like this one, and the van never had the issue again. It’s a reminder that intermittent electrical faults are often the first sign of a dying module.
Is Your Van Exhibiting These Telltale Signs?
A failing ECM can manifest in various ways. If you’re experiencing any of the following, it’s a strong indicator that the engine’s computer needs attention. Look out for:
- ✔ Check Engine Light is illuminated with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained drops in fuel efficiency.
- ✔ Rough idling, engine stumbling, or hesitation during acceleration.
- ✔ Stalling for no apparent reason, either at a stop or while driving.
- ✔ Transmission shifting issues or harsh engagement.
- ✔ Loss of communication with other vehicle modules, triggering various warning lights.
A Straightforward Guide to Installation
Installing your new 2016 Savana 3500 ECM is a manageable job for a DIYer or professional technician. Since it arrives pre-programmed, no special scan tools are needed for the initial setup.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electrical work.
- Locate the ECM: On the 2016 Savana and Express vans, the ECM is typically located in the left-hand (driver’s side) rear corner of the engine compartment.
- Disconnect the Harnesses: Carefully release the locking tabs on the electrical connectors and pull them straight out from the module. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware as you will need it for the new module.
- Install the New ECM: Mount the new module securely onto the bracket and re-tighten the bolts.
- Reconnect Everything: Firmly plug the electrical harnesses back into the new ECM until they click into place. Reconnect the negative battery terminal.
- Final Step: 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. The vehicle is now ready to start.
Verified Compatibility Across a Range of GM Vehicles
While this is the correct 2016 Savana 3500 ECM, this module, part number 12643636, is also the specified component for a wide array of other General Motors vehicles. Our VIN-specific programming ensures it functions perfectly for your application. Please verify your part number or contact us with your VIN. This module fits:
- ✔ Chevrolet Cruze (2012-2016)
- ✔ Chevrolet Sonic (2012-2016)
- ✔ Chevrolet Trax (2013-2016)
- ✔ Chevrolet Spark (2014-2015)
- ✔ Chevrolet Volt (2011-2015)
- ✔ Chevrolet ELR (2014-2016)
- ✔ Chevrolet Express 2500/3500 Van (2016 with 4.8L or 6.0L)
- ✔ GMC Savana 2500/3500 Van (2016 with 4.8L or 6.0L)
- ✔ Chevrolet Silverado 2500/3500 Pickup (2012-2016 with 6.0L)
- ✔ GMC Sierra 2500/3500 & Denali Pickup (2012-2016 with 6.0L)
- ✔ Chevrolet Suburban 3500 (2016)
- ✔ Buick Encore (2013-2016)
Frequently Asked Questions
How do I provide my VIN for programming?
After you complete your purchase, you will receive instructions to send us your vehicle’s 17-digit VIN. We cannot ship the module until we receive this information, as the programming is essential for the part to function correctly.
Is any additional programming required after installation?
No. This ECM comes fully programmed with the latest GM software based on your VIN. In most cases, it is a plug-and-play installation. Some vehicles may require a security relearn procedure, which can typically be done without special tools by cycling the key.
Will this fix my specific check engine light codes?
This module will correct issues directly caused by a faulty ECM, such as internal processor faults (P0601, P0606) or communication errors (U-codes). However, it’s crucial to ensure the underlying cause of other codes (e.g., sensor failures) has been properly diagnosed and repaired first.
What is the difference between an ECM and a PCM?
The terms are often used interchangeably. ECM stands for Engine Control Module, while PCM means Powertrain Control Module. In most modern vehicles, a single PCM controls both the engine and the transmission. This part serves that function.
How do I confirm this is the right part for my vehicle?
The best way is to match the part number from your existing module. This ECM replaces several part numbers including 12643636, 12668866, 12668994, and more. If you are unsure, please send us your VIN, and we will happily verify compatibility for you.