Restore Peak Performance to Your Sierra Denali
Is your 2017-2018 Sierra Denali 1500 running rough, stalling unexpectedly, or flashing a persistent check engine light? A failing Engine Control Module (ECM) is often the culprit, acting like a confused brain for your truck’s sophisticated engine. This isn’t just an annoyance; it affects fuel economy, power, and reliability. We offer a direct, dependable solution: a replacement ECM, part number 12674052, programmed specifically for your vehicle before it ever leaves our facility.
Forget the hassle and high cost of a dealership visit for programming. Simply provide us with your vehicle’s VIN during checkout, and our expert technicians will flash this module with the latest, most stable GM factory calibrations. This ensures that when the part arrives, it’s ready to communicate with your truck’s specific systems. This is the most efficient way to get your vehicle back to factory-spec operation.
Case Study: A Tricky Diagnosis
A customer brought in a 2017 Silverado with a frustrating issue: it would randomly lose throttle response and throw a U0100 (Lost Communication with ECM/PCM) code, but only on hot days. We checked wiring and connectors, which all seemed fine. After swapping in a test module, the problem vanished. The original ECM had an internal hairline fracture on the circuit board that would separate when it expanded with heat, breaking communication. Replacing the ECM with a properly programmed unit like this one was the definitive fix, saving the customer from chasing intermittent electrical gremlins for weeks.
Is Your Truck Showing These Symptoms?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, it’s a strong indicator that the brain of your engine needs attention. Look out for:
- ✔ Unexplained drop in fuel efficiency
- ✔ Engine stalling, stuttering, or misfiring
- ✔ Difficulty starting or a complete no-start condition
- ✔ The check engine light is on with codes like P0601, P0606, or U0100
- ✔ Poor or erratic automatic transmission shifting
- ✔ Loss of power and sluggish acceleration
Your Straightforward Installation Guide
Installing your new 2017-2018 Sierra Denali 1500 ECM is a manageable job for a confident DIYer or any professional mechanic. Follow these steps carefully for a successful replacement.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes to allow all systems to power down completely.
- Locate the ECM: On most GM trucks like the Sierra and Silverado, the ECM is found in the engine compartment, typically on the driver’s side near the firewall or airbox.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs that need to be released. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed ECM into place. Securely reconnect the electrical harnesses, ensuring they click and lock into position.
- Reconnect the Battery: Reattach the negative battery terminal and tighten it securely.
- Perform Relearn Procedures: This is a critical final step. You will need to perform the Vehicle Theft Deterrent (VTD) relearn using a compatible scan tool with access to GM’s TIS2Web or Techline Connect service. The vehicle will not start until this security handshake is completed. Other procedures like a crankshaft variation relearn may also be necessary.
Verified Vehicle Compatibility
This Engine Control Module is a direct-fit replacement for a wide range of GM vehicles. It is compatible with part numbers 12692068, 12704476, 12686382, 12674052, 12674472, and 12678815. Please confirm your vehicle is on the list below for guaranteed compatibility.
- 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 Corvette
- 2017 Chevrolet Tahoe & Suburban 1500
- 2016-2018 Chevrolet Silverado 1500 Pickup
- 2017 GMC Yukon & Yukon XL 1500
- 2016-2018 GMC Sierra 1500 Pickup
- 2017-2018 GMC Sierra Denali 1500
Frequently Asked Questions
Frequently Asked Questions
Why do you need my VIN?
Your VIN (Vehicle Identification Number) is essential. We use it to load the precise, factory-correct software and calibrations for your truck’s specific engine, transmission, and options. This ensures seamless integration and performance, saving you a trip to the dealer for programming.
What is a Vehicle Theft Deterrent (VTD) relearn?
The VTD relearn is a security procedure that syncs the new ECM to your vehicle’s ignition key and security system. Without this step, the truck’s anti-theft system will prevent the engine from starting. This procedure requires a professional scan tool with access to GM’s software, like Techline Connect.
Can I do the theft relearn myself?
While some older GM models had a manual key-cycle relearn, vehicles from this era require a diagnostic tool with a subscription to GM’s service. This is typically performed by a professional mechanic or a well-equipped DIY enthusiast. It is the buyer’s responsibility to have this procedure completed.
Is this a plug-and-play part?
It is ‘plug-and-program-ready’. The physical installation is straightforward, and the main engine software is pre-loaded. However, the mandatory security relearn procedure must be performed on the vehicle after installation for it to function.
Will this fix my check engine light?
If the check engine light and performance issues are caused by an internal failure of the original ECM (e.g., codes P0601-P0606), then yes, this part is the correct fix. However, it will not fix issues caused by other faulty components like sensors or wiring. Proper diagnosis is key.