Restore Peak Performance and Reliability to Your GM Vehicle
Is your Buick Encore, Chevy Cruze, or another compatible GM vehicle suffering from frustrating, hard-to-diagnose issues? A faulty Engine Control Module (ECM) is often the culprit behind problems like random stalling, no-start conditions, erratic engine behavior, and a persistent Check Engine Light. As the central computer for your engine, its proper function is non-negotiable. This replacement ECM, part number 12663405, is the definitive solution to get your vehicle running smoothly and efficiently again.
We take the guesswork and hassle out of the repair. Unlike a generic part from a salvage yard or a big-box store, each module we ship is professionally programmed with the latest official GM software updates, tailored specifically to your vehicle’s VIN. This critical step ensures that all systems—from fuel delivery and ignition timing to transmission shifting and emissions controls—operate exactly as the factory intended. You get a reliable, plug-and-play solution without the exorbitant cost and scheduling headaches of a dealership visit.
Case Study: A Tricky Diagnosis
I once had a 2014 Chevy Sonic in my bay that was a real head-scratcher. The owner complained of intermittent power loss and a flashing Check Engine Light, but the codes were inconsistent. One day it would be a misfire code, the next an O2 sensor fault. We checked wiring, sensors, and fuel pressure—all were fine. The issue felt like a ghost in the machine. On a hunch, we monitored the ECM’s live data and noticed erratic processor activity. We replaced the old module with a VIN-programmed unit like this one. The difference was immediate. All the random codes vanished, the engine ran perfectly, and the customer was thrilled to have their reliable car back. It’s a classic example of how a failing ECM can send you chasing phantom problems, and why a correctly programmed, quality replacement is the only real fix.
Is Your GM Vehicle Showing These Signs?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, it’s a strong indicator that your engine’s computer needs attention:
- âś” Check Engine Light is on with codes like P0601, P0602, P0606, or U0100
- âś” Engine cranks but refuses to start
- âś” Unexplained drops in fuel economy
- âś” Rough or unstable idling
- âś” Vehicle stalls unexpectedly while driving or at a stop
- âś” Noticeable loss of power and poor acceleration
- âś” Harsh or incorrect automatic transmission shifting
- âś” Failure to pass an emissions inspection
Plug-and-Play Installation: Get Your Vehicle Running Right
Installing your new, pre-programmed ECM is a straightforward process that a confident DIYer can handle. Just follow these general steps:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes for the system capacitors to discharge.
- Locate the ECM: The location varies by model. On many vehicles like the Chevy Cruze or Buick Encore, it’s in the engine bay. On others like the Volt or Express Van, it may be in the rear compartment. Consult a repair manual for your specific vehicle.
- Disconnect Connectors: Carefully release the locking tabs on the electrical wiring harnesses and pull them straight out from the module. Do not force them.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep track of the hardware as you will reuse it.
- Install the New Module: Mount your new ECM securely onto the bracket and tighten 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: In most cases, the vehicle will start and run correctly immediately. Some vehicles may require a simple security relearn procedure, which can typically be done without special tools (instructions are widely available online or in your owner’s manual).
Verified Compatibility for a Wide Range of GM Models
This module is a direct replacement for multiple part numbers, including 12668866, 12668994, 12643636, 12670335, 22819494, and 12692200. It is guaranteed to fit the following vehicles with the specified options:
Buick:
ENCORE 13-14 (1.4L)
ENCORE 15 (1.4L), ID 12643636 or 12668866
ENCORE 16 (1.4L), VIN B (8th digit, opt LUV)
Cadillac:
ELR 14-16 (Gasoline, LH rear engine compartment)
Chevrolet:
CRUZE 12 (1.4L)
CRUZE 13-14 (Gasoline)
CRUZE 15 (Gasoline), ID 12643636 or 12668866
CRUZE 16 (VIN P, 4th digit, Limited)
EXPRESS 2500/3500 VAN 16 (4.8L or 6.0L)
SILVERADO 2500/3500 PICKUP 12-16 (6.0L)
SONIC 12 (1.4L)
SONIC 13-14 (ID 12643636)
SONIC 15 (ID 12643636 or 12668866)
SONIC 16
SPARK 14-15 (Gasoline model)
SUBURBAN 3500 16
TRAX 13-16
VOLT 11-15 (Gasoline, LH rear engine compartment)
GMC:
SAVANA 2500/3500 VAN 16 (4.8L or 6.0L)
SIERRA 2500/3500 PICKUP 12-16 (6.0L)
SIERRA DENALI 2500 12-15 (6.0L)
SIERRA DENALI 3500 12-16 (6.0L)
Frequently Asked Questions
What is an ECM?
The Engine Control Module (ECM), sometimes called a Powertrain Control Module (PCM), is a powerful computer that controls all aspects of your vehicle’s engine performance, including fuel mixture, spark timing, and emissions systems, to ensure optimal power and efficiency.
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential. We use it to load the exact, correct software and calibrations from GM for your specific vehicle’s engine, transmission, and factory options. This ensures a perfect match and seamless operation upon installation.
Is any additional programming required after installation?
No. This module arrives pre-programmed and ready to install. In some rare cases, a simple ‘key relearn’ or ‘security relearn’ procedure may be needed, which typically involves turning the key in a specific sequence and does not require special tools.
How do I provide my VIN?
After you complete your purchase, simply send us a message with your 17-digit VIN. We cannot program and ship your part until we receive this information, so please provide it promptly to avoid delays.
What if my original part number is slightly different?
This module is a direct replacement for several part numbers, including 12668866, 12668994, 12643636, and more. As long as your vehicle is on the compatibility list, this module will function correctly once programmed to your VIN.
Is this a reliable, long-term fix?
Absolutely. We provide high-quality components programmed with the latest stable software from the manufacturer. This is designed to be a durable and dependable solution to your vehicle’s electronic issues.