Is Your GM Vehicle Running Rough or Not Starting?
The Engine Control Module (ECM), often called the engine computer, is the central command center for your vehicle’s engine. It controls everything from fuel mixture and ignition timing to transmission shifts and emissions systems. When the ECM begins to fail, it can cause a wide range of confusing and frustrating problems, often leaving you stranded. If you’re experiencing erratic engine behavior, a persistent check engine light, or a no-start condition in your 2018 GMC Yukon XL, Chevrolet Silverado, Corvette, or other compatible GM model, a faulty ECM is a likely culprit.
This isn’t just a replacement part; it’s a direct solution. We are offering a genuine GM Engine Control Module, part number 12704475, which is the latest, most updated replacement for several older part numbers including 12692069, 12680656, 12686383, and 12688528. The most critical service we provide is programming this module specifically for your vehicle using your Vehicle Identification Number (VIN). This ensures that the computer has the correct factory calibrations and software updates from GM, making the installation process as smooth as possible.
From the Diagnostic Bay
We had a 2018 Sierra 1500 come into the shop with a bizarre issue. The owner complained of intermittent stalling at stoplights and a check engine light that would come and go. We scanned it and got a slew of communication error codes that didn’t point to a single sensor. After hours of chasing wires and checking grounds, we suspected the ECM. The problem was, a new, unprogrammed module would have required expensive dealer-level programming. We sourced a pre-programmed module like this one, keyed to the truck’s VIN. After installation and performing the security relearn, the truck started right up and ran perfectly. All the ghost codes vanished. It saved the customer hundreds of dollars and significant downtime compared to a trip to the dealership.
Symptoms of a Failing Engine Control Module
- ✔ Check Engine Light is on with various, often inconsistent, trouble codes.
- ✔ Vehicle will not start or is very difficult to start.
- ✔ Poor engine performance, including stuttering, stalling, or hesitation.
- ✔ Noticeable decrease in fuel economy.
- ✔ Transmission shifting issues or failure to shift properly.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Intermittent issues that seem to have no logical cause.
The Right Solution: A Programmed 2018 Yukon XL ECM
Don’t settle for a generic, unprogrammed module that will require additional, costly programming at a dealership or specialized shop. Our process is designed to get you back on the road faster. By providing us with your VIN at the time of purchase, you receive a 2018 Yukon XL ECM that is ready for installation and the final vehicle-side setup procedures. This module is loaded with the newest software updates available from GM, which can often resolve underlying drivability issues that were present even before the original module failed. This is the most effective way to ensure all engine and powertrain systems function exactly as the manufacturer intended.
Installation and Required Relearn Procedures
Please be aware that while the module comes programmed to your VIN, installation is not always a simple plug-and-play process. Modern vehicles have sophisticated anti-theft systems that are tied to the ECM. Upon installation, a Vehicle Theft Deterrent System relearn is mandatory. If this procedure is not performed, the vehicle will not start. This relearn must be done using a professional GM programming system, such as Tis2web or Techline Connect.
Additionally, other vehicle-specific procedures may be necessary depending on your model and its options. These can include a Crankshaft Variation Relearn, injector flow rate programming, or other setup procedures. It is the responsibility of the buyer or their technician to perform these final steps. We provide the correctly calibrated brain; the final handshake with your vehicle’s systems must be completed on-site.
Guaranteed Fitment and Part Number Compatibility
This ECM, part number 12704475, is the correct service replacement for a wide range of GM vehicles. If your original module has any of the following part numbers, this unit is the correct replacement for you:
- 12704475
- 12692069
- 12680656
- 12686383
- 12688528
This module fits the following vehicles:
- 2018-2019 Corvette
- 2018 Silverado 1500 & Sierra 1500 / Denali 1500
- 2018 Escalade & Escalade ESV
- 2018 Express 2500/3500 & Savana 2500/3500 (4.3L)
- 2018 Suburban 1500 & Tahoe
- 2018 Yukon & Yukon XL 1500
- 2018 XTS (3.6L)
Frequently Asked Questions
Is this ECM ready to install right out of the box?
Almost. It comes programmed to your VIN, but you MUST perform a vehicle theft deterrent relearn after installation for the vehicle to start. Other relearns, like for the crankshaft position sensor, may also be required.
How do I provide my VIN?
After you complete your purchase, we will send you instructions on how to submit your vehicle’s 17-digit VIN. We cannot program or ship the module without it.
Can I do the theft relearn myself?
The theft relearn for these vehicles requires a professional-grade tool with a subscription to GM’s programming software (like Tis2web/Techline Connect). It is typically performed by a qualified automotive technician or dealership.
What happens if I don’t perform the relearn procedures?
If the theft relearn is not completed, the vehicle’s security system will prevent it from starting. If other procedures like the crank relearn are skipped, the engine may run poorly and the check engine light will likely illuminate.
Is this a used part?
This is a high-quality, tested replacement part that has been programmed with the latest GM software for your specific vehicle. It is guaranteed to function correctly once installed and all necessary relearn procedures are completed.