Restore Peak Performance to Your GM Vehicle
Is your Escalade, Sierra, or Tahoe suffering from frustrating issues like intermittent stalling, a persistent check engine light, or a complete no-start condition? Before you assume the worst, the problem often lies with a faulty Engine Control Module (ECM). As the central computer of your vehicle, a failing ECM can cause a wide range of performance problems. This genuine GM Engine Control Module, part number 12678815, is the reliable, direct-fit solution to get your vehicle running smoothly again.
We take the guesswork out of the repair. Unlike a generic part off the shelf, we program this module specifically for your vehicle using your VIN. This ensures it has the latest factory software calibrations from GM, tailored to your exact make, model, and options. This critical step is essential for proper engine function, fuel economy, and emissions control.
From the Diagnostic Bay
I recently had a 2017 Silverado 1500 in the shop with a complaint that stumped two other mechanics. The truck would run perfectly for days, then suddenly die at a stoplight and refuse to restart for an hour. There were no consistent trouble codes, just a generic U0100 ‘Lost Communication with ECM’ code that would appear and disappear. After checking all the wiring and grounds, we tested the ECM itself. We found that heat soak was causing an internal failure. We replaced it with one of these pre-programmed modules, performed the security relearn, and the truck has been running flawlessly ever since. Getting a module programmed to the VIN beforehand saved the customer significant time and diagnostic headaches.
Common Signs of a Failing ECM
If you’re experiencing any of the following, a faulty ECM could be the culprit. Replacing it with a quality, correctly programmed module is often the definitive fix.
- ✔ Check Engine Light is on with communication codes (e.g., U0100) or internal processor codes (P0601, P0606).
- ✔ Engine cranks but will not start.
- ✔ Intermittent stalling or rough idling for no apparent reason.
- ✔ Noticeable decrease in fuel economy.
- ✔ Poor engine performance, hesitation, or misfires.
- ✔ Automatic transmission shifting issues.
A Straightforward Guide to Installation
Installing your new 2017 Escalade Engine Control Module is a manageable job for a seasoned DIYer or any professional technician. Follow these general steps for a successful replacement.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electrical work.
- Locate the ECM: On most compatible trucks and SUVs like the Tahoe or Sierra, the ECM is located in the engine compartment on the driver’s side. On other models like the Corvette, it may be in the passenger-side cowl area.
- Disconnect and Remove: Carefully unplug the wiring harness connectors. They have locking tabs that must be released. Once disconnected, unbolt the old module from its mounting bracket and remove it.
- Install the New Module: Bolt the new, pre-programmed ECM into place. Reconnect the wiring harnesses, ensuring they click securely into place.
- Reconnect Battery: Reattach the negative battery terminal.
- Perform Relearn Procedures: This is a critical final step. If the vehicle does not start, you must perform the Vehicle Theft Deterrent System relearn using a compatible scan tool with access to GM’s TIS2WEB or Techline Connect service. Other procedures like a crankshaft variation relearn may also be necessary.
IMPORTANT: Post-Installation Requirements
IMPORTANT: Post-Installation Requirements
This ECM is sold pre-programmed to your vehicle’s VIN with the correct GM calibrations. However, it is the buyer’s responsibility to perform any necessary post-installation procedures. This includes, but is not limited to, the Vehicle Theft Deterrent System (VTD) relearn, crankshaft position variation relearn, and any other setup procedures required by your specific vehicle. These procedures require professional-level scan tools and software access (e.g., GM Techline Connect).
Verified Vehicle Compatibility
This module is a direct replacement for part numbers 12692068, 12704476, 12686382, 12674052, 12674472, and 12678815. It is confirmed to fit the following vehicles:
- ✔ 2017 Cadillac ESCALADE / ESCALADE ESV
- ✔ 2017 Cadillac XTS (3.6L Twin Turbo, VIN 8)
- ✔ 2017 Cadillac CTS (6.2L Supercharged or 3.6L Twin Turbo)
- ✔ 2017 Cadillac ATS (3.6L, VIN Y)
- ✔ 2017 Chevrolet TAHOE / SUBURBAN 1500
- ✔ 2017 Chevrolet CORVETTE
- ✔ 2016-2018 Chevrolet SILVERADO 1500 PICKUP (check specific IDs)
- ✔ 2017 GMC YUKON / YUKON XL 1500
- ✔ 2016-2018 GMC SIERRA 1500 PICKUP / SIERRA DENALI 1500 (check specific IDs)
Frequently Asked Questions
IMPORTANT: Post-Installation Requirements
This ECM is sold pre-programmed to your vehicle’s VIN with the correct GM calibrations. However, it is the buyer’s responsibility to perform any necessary post-installation procedures. This includes, but is not limited to, the Vehicle Theft Deterrent System (VTD) relearn, crankshaft position variation relearn, and any other setup procedures required by your specific vehicle. These procedures require professional-level scan tools and software access (e.g., GM Techline Connect).