Restore Peak Performance and Reliability to Your GM Vehicle
Is your truck or van suddenly running rough, refusing to start, or flashing a check engine light that has you and your mechanic chasing ghosts? A faulty Engine Control Module (ECM), the vehicle’s central computer, is often the hidden culprit behind these frustrating and complex issues. This isn’t just a replacement part; it’s a direct solution. We are offering a genuine GM Engine Control Module, part number 12668991, that arrives at your door pre-programmed with the latest factory software specifically for your vehicle. Simply provide your Vehicle Identification Number (VIN) at checkout, and we handle the complex programming for you, saving you a costly trip to the dealership and hours of diagnostic headaches.
As a technician with over two decades of experience, I’ve seen firsthand how a failing ECM can mimic a dozen other problems. A customer might spend hundreds on new sensors and wiring repairs, only for the issue to persist. The root cause? An internal fault in the ECM that a standard scan tool can’t always pinpoint. This module is the definitive fix for those hard-to-diagnose drivability problems, ensuring your engine gets the precise fuel, spark, and timing commands it needs to run as the engineers intended. By installing this pre-flashed 2016 Suburban 3500 Engine Control Module, you’re not just replacing a part—you’re restoring your vehicle’s electronic nervous system to perfect health.
A Technician’s Notebook: The Case of the Intermittent No-Start
I once had a 2014 Silverado 2500 in the bay with a problem that drove the owner crazy: it would randomly refuse to start. No crank, no click, nothing. Then, an hour later, it would fire right up. We checked the battery, starter, and ignition switch—all perfect. The scan tool showed a U0100 Lost Communication with ECM code, but only intermittently. After tracing the CAN bus network wiring and finding no faults, we focused on the module itself. We swapped in a VIN-programmed ECM, and the problem vanished instantly. The original module had a hairline fracture on the circuit board that would separate when it got hot, breaking communication. This is a classic failure mode that only a direct replacement can solve.
Is Your GM Vehicle Showing These Signs of ECM Failure?
- ✔ The engine will crank but refuses to start.
- ✔ A persistent Check Engine Light (CEL) is illuminated on your dash.
- ✔ Your vehicle experiences stalling, surging, or a rough, inconsistent idle.
- ✔ You notice a sudden and unexplained drop in fuel economy.
- ✔ The automatic transmission shifts harshly or at the wrong times.
- ✔ Your scan tool shows communication error codes (e.g., U0100) or internal processor fault codes (e.g., P0601, P0606).
- ✔ Complete loss of spark or fuel injector pulse.
A Straightforward Guide to Your ECM Installation
Replacing the 2016 Suburban 3500 Engine Control Module is a manageable job for a DIYer with basic tools. Follow these steps carefully for a successful installation.
- 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 Module: On most GM trucks and vans like the Suburban, Silverado, and Express, the ECM is located in the engine compartment, typically on the driver’s side near the firewall or inner fender.
- Disconnect and Remove: Carefully unplug the electrical connectors. These usually have locking tabs that need to be released. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Mount your new, pre-programmed ECM onto the bracket and securely tighten the bolts. Reconnect the electrical connectors, ensuring they click firmly into place.
- Power Up: Reconnect the negative battery terminal and tighten it securely.
- Security Relearn Procedure: In many cases, a simple security relearn procedure is required for the vehicle to recognize the new ECM. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times before starting the engine. Consult your vehicle’s service information for the exact procedure.
Verified Compatibility Across a Wide Range of GM Vehicles
This ECM is a direct-fit replacement for numerous GM cars, trucks, and vans. It is a compatible replacement for part numbers 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200. Please verify your vehicle from the list below to ensure proper fitment.
CRUZE 16 Electronic Control Module; VIN P (4th digit, Limited)
SONIC 12 Electronic Control Module; 1.4L
ELR 14-16 Electronic Control Module; gasoline, (LH rear engine compartment)
EXPRESS 3500 VAN 16 Electronic Control Module; (LH rear engine compartment), 4.8L
CRUZE 12 Electronic Control Module; 1.4L
CRUZE 15 Electronic Control Module; gasoline, ID 12668866
SONIC 15 Electronic Control Module; ID 12668866
TRAX 13-14 Electronic Control Module; 1.4L
SONIC 13 Electronic Control Module; ID 12643636
EXPRESS 3500 VAN 16 Electronic Control Module; (LH rear engine compartment), 6.0L
SAVANA 3500 VAN 16 Electronic Control Module; (LH rear engine compartment), 6.0L
EXPRESS 2500 VAN 16 Electronic Control Module; (LH rear engine compartment), 6.0L
SONIC 14 Electronic Control Module; (ID 12643636)
EXPRESS 2500 VAN 16 Electronic Control Module; (LH rear engine compartment), 4.8L
SILVERADO 2500 PICKUP 12-16 Electronic Control Module; (LH front engine compartment), 6.0L
SILVERADO 3500 PICKUP 12-16 Electronic Control Module; (LH front engine compartment), 6.0L
VOLT 11-15 Electronic Control Module; gasoline, (LH rear engine compartment)
SAVANA 2500 VAN 16 Electronic Control Module; (LH rear engine compartment), 4.8L
CRUZE 14 Electronic Control Module; gasoline
SAVANA 2500 VAN 16 Electronic Control Module; (LH rear engine compartment), 6.0L
SONIC 16 Electronic Control Module
CRUZE 13 Electronic Control Module
ENCORE 15 Electronic Control Module; (1.4L), ID 12643636
ENCORE 16 Electronic Control Module; (1.4L), VIN B (8th digit, opt LUV)
SAVANA 3500 VAN 16 Electronic Control Module; (LH rear engine compartment), 4.8L
SIERRA 2500 PICKUP 12-16 Electronic Control Module; (LH front engine compartment), 6.0L
SIERRA 3500 PICKUP 12-16 Electronic Control Module; (LH front engine compartment), 6.0L
TRAX 15-16 Electronic Control Module
SIERRA DENALI 2500 12-15 Electronic Control Module; (LH front engine compartment), 6.0L
SUBURBAN 3500 16 Electronic Control Module; (LH front engine compartment)
ENCORE 13-14 Electronic Control Module; (1.4L)
SPARK 14-15 Electronic Control Module; gasoline model
SIERRA DENALI 3500 12-16 Electronic Control Module; (LH front engine compartment), 6.0L
ENCORE 15 Electronic Control Module; (1.4L), ID 12668866
SONIC 15 Electronic Control Module; ID 12643636
Choosing this pre-programmed 2016 Suburban 3500 Engine Control Module is the most efficient way to get your vehicle back on the road, running smoothly and reliably for years to come.
Why do I need to provide my VIN?
Your VIN is essential for us to program the module with the exact software and calibrations for your vehicle’s specific engine, transmission, and options. This ensures seamless communication with other modules and correct engine operation.
Is any additional programming required after installation?
No! This module arrives pre-programmed and ready for installation. In some cases, a simple, tool-free ‘security relearn’ procedure may be needed, which you can do yourself in about 30 minutes.
What if my original part number isn’t on the list?
Please contact us with your VIN and original part number. This ECM replaces several different numbers, and we can verify compatibility for you to ensure you get the correct part.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the ECM (common codes P0600-P0606) or a related communication error (U-codes), this module is the correct fix. It’s crucial to properly diagnose the issue before ordering to ensure the ECM is the root cause.
What tools are needed for the job?
Typically, you’ll only need basic hand tools, such as a socket set and ratchet, to remove the mounting bolts and disconnect the battery. No special electronic equipment is required.