As a technician with over two decades of experience, I know that when a workhorse like your 2016 Savana 3500 Van goes down, every minute of downtime costs you money and peace of mind. If you’re dealing with baffling electrical issues, a persistent check engine light, or a van that just won’t start, a failing Engine Control Module (ECM) is often the culprit. This isn’t just a part; it’s the brain of your vehicle’s engine, and when it falters, everything grinds to a halt.
This replacement Engine Control Module, part number 12663405, is the reliable, straightforward solution you need. We take the guesswork and dealer-level expense out of the equation. Before we ship this module to you, our team programs it with the latest GM software updates, specifically matched to your van’s Vehicle Identification Number (VIN). This means it arrives ready to install, eliminating the need for expensive scan tools or a trip to the dealership for programming. It’s a direct-fit replacement designed to restore your engine’s performance, fuel efficiency, and dependability.
A Technician’s Notebook: The Intermittent No-Start Nightmare
A local contractor brought in his 2016 Savana 6.0L that was causing him major headaches. The van would randomly refuse to start. Sometimes it would crank but not fire; other times, it was completely dead. He had already replaced the battery and checked the starter. When I connected my scan tool, I found a slew of communication error codes (U0100 – Lost Communication With ECM/PCM) and a history code for P0601 (Internal Control Module Memory Check Sum Error). The P0601 was the smoking gun. This code almost always points to an internal failure of the ECM itself. The intermittent nature of the problem was caused by a failing processor on the circuit board. We installed a VIN-programmed module, and the van fired up on the first try, every time. It’s a classic failure mode I’ve seen countless times on these hardworking GM vans.
Is Your Savana Van Showing These Signs?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, it might be time for a replacement 2016 Savana 3500 ECM.
- ✔ Check Engine Light is on with codes pointing to module failure (e.g., P0601, P0606).
- ✔ Engine cranks but will not start.
- ✔ Intermittent stalling or rough idling for no apparent reason.
- ✔ A noticeable drop in fuel economy.
- ✔ The vehicle is in “limp mode,” with reduced power.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Automatic transmission shifting issues or harsh shifts.
A Straightforward Guide to Installation
Installing your new 2016 Savana 3500 ECM is a manageable job for a DIYer with basic tools. Following these steps ensures a safe and successful replacement.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental reconnection.
- Locate the ECM: On the 2016 Savana Van, the Engine Control Module is typically found in the left-hand (driver’s side) rear of the engine compartment.
- Disconnect the Connectors: Carefully release the locking tabs on the electrical wiring harnesses and gently pull them straight out from the module. Never force them. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the mounting hardware, as you will need it for the new module.
- Install the New Module: Mount the new, pre-programmed ECM onto the bracket and secure it with the original hardware.
- 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 for 10-15 seconds before starting the engine. This allows the other vehicle modules to recognize the new ECM. Start your van and check for proper operation.
Verified Vehicle Compatibility
This module is a direct replacement for service number 12663405 and is compatible with a wide range of GM vehicles. Please verify your part number and vehicle in the list below. This unit is guaranteed to fit your 2016 Savana 3500 ECM for both 4.8L and 6.0L engines.
CHEVROLET CRUZE 12-15 (1.4L, 1.8L options)
CHEVROLET SONIC 12-16 (1.4L options)
CHEVROLET TRAX 13-16 (1.4L)
CHEVROLET SPARK 14-15 (Gasoline model)
CHEVROLET VOLT 11-15
CADILLAC ELR 14-16
BUICK ENCORE 13-16 (1.4L)
GMC/CHEVROLET EXPRESS & SAVANA 2500/3500 VANS 16 (4.8L, 6.0L)
GMC/CHEVROLET SILVERADO & SIERRA 2500/3500 PICKUPS 12-16 (6.0L)
CHEVROLET SUBURBAN 3500 16
Note: This is a summary. This module replaces part numbers 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200. Always confirm your original part number for 100% compatibility.
Frequently Asked Questions
What is VIN programming and why is it necessary?
VIN programming loads your vehicle’s specific software onto the ECM. This ensures the module communicates correctly with your engine, transmission, and security system (Pass-Key/VATS). We do this for you, so the part is ready for installation upon arrival, saving you a trip to the dealer.
How do I provide my VIN number?
After you complete your purchase, you will receive instructions to send us your 17-digit VIN. We cannot ship your order until we receive this information, as the programming is essential for the part to function in your van.
Will I need to perform any other procedures after installation?
In most cases, no. Our programming handles the critical setup. For some GM vehicles, a security relearn procedure may be needed, which can typically be done without special tools. Instructions are readily available online or in service manuals if required.
Is this a reliable, tested part?
Absolutely. Each module is thoroughly inspected and tested to ensure it meets or exceeds OEM specifications for performance and reliability. You are getting a quality component that provides a dependable fix.
What if my part number is slightly different?
This ECM is a direct replacement for several part numbers, including 12668866, 12668994, 12643636, and others listed. As long as your vehicle is on the compatibility list and your original part number is one of the alternates, this module will work perfectly.