Restore Your GM Truck’s Brain and Get Back on the Road with Confidence
Is your 2015-2016 GMC Yukon XL 1500 acting erratically? Experiencing frustrating issues like a persistent check engine light, sudden stalling, rough idling, or a complete no-start condition? The problem often points to a failing Engine Control Module (ECM), the central computer that manages your engine’s performance, fuel delivery, and emissions. When it falters, your entire vehicle suffers. This isn’t just an inconvenience; it’s a reliability issue that can leave you stranded. This replacement ECM is the dependable, straightforward solution to restore your vehicle’s factory performance and peace of mind.
Case Study: A Tricky Diagnosis
I recently had a 2015 Sierra 1500 (which uses this exact same ECM) in my bay with a maddeningly intermittent no-start problem. The owner had already replaced the battery and starter. The truck would crank but wouldn’t fire, and then an hour later, it would start perfectly. There were no consistent trouble codes, just a few random communication faults (U-codes) stored in history. After checking all the power and ground circuits to the ECM, I noticed a slight voltage drop on a key sensor reference wire *only* when the module was hot. This internal fault was causing the computer to intermittently fail its own startup checks. Swapping in a pre-programmed ECM like this one resolved the issue instantly. It’s a classic example of how a failing ECM can create ghost-like problems that are a nightmare to diagnose without seeing it firsthand.
The Dealership Alternative That Saves You Time and Money
Forget the hassle and high cost of a dealership visit. Ordering an ECM from the dealer means paying a premium for the part, additional labor costs for installation, and a separate, often expensive, fee for programming. Our process simplifies everything. We send you a high-quality 2015-2016 Yukon XL ECM that is professionally flashed with the latest official GM software updates. All we need is your vehicle’s VIN to ensure the calibration is a perfect match for your specific engine, transmission, and options. It arrives at your door ready for installation, eliminating the need for specialized programming tools or a trip to the service center.
Is Your Yukon XL Showing These Telltale Signs?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, a faulty engine computer is a very likely culprit:
- ✔ Persistent Check Engine Light (CEL) with internal processor codes (e.g., P0601, P0603, P0606) or communication codes (U0100).
- ✔ Unexplained stalling, especially after the engine warms up.
- ✔ Rough or unstable idle.
- ✔ Noticeable decrease in fuel economy.
- ✔ Engine cranks but refuses to start.
- ✔ Transmission shifting issues or harsh engagement.
- ✔ Seeming loss of power or poor acceleration.
A Straightforward Guide to Installation
For the confident DIYer or professional technician, swapping the ECM is a manageable job. On most GM trucks and SUVs of this era, the ECM is located in the engine bay, making it accessible.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 10 minutes for all system capacitors to discharge.
- Locate the ECM: On your Yukon XL, the ECM is typically found in the front left (driver’s side) of the engine compartment.
- Disconnect Connectors: Carefully unlatch and remove the main wiring harness connectors from the old ECM. Inspect them for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed ECM securely onto the bracket.
- Reconnect and Secure: Firmly plug the wiring harness connectors into the new ECM until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn: In many cases, you may need to perform a simple security relearn procedure. 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 owner’s manual for the specific procedure for your vehicle.
Verified Vehicle Compatibility
This module is a direct replacement for part number 12663391 and is compatible with a wide range of GM vehicles and other interchangeable part numbers. Please verify your vehicle is on this list. This unit is guaranteed to fit the following models:
- Cadillac ATS: 2014-2016 (3.6L)
- Cadillac CTS: 2014-2016 (3.6L, 6.2L)
- Cadillac Escalade / ESV: 2015-2016
- Cadillac XTS: 2014-2016 (3.6L)
- Chevrolet Camaro: 2016 (6.2L)
- Chevrolet Colorado: 2015-2016 (3.6L)
- Chevrolet Corvette: 2014-2016
- Chevrolet Silverado 1500: 2014-2016
- Chevrolet Suburban 1500: 2015-2016
- Chevrolet Tahoe: 2015-2016
- GMC Canyon: 2015-2016 (3.6L)
- GMC Sierra 1500 / Denali 1500: 2014-2016
- GMC Yukon / Yukon XL 1500: 2015-2016
This module also interchanges with part numbers: 12692067, 12676230, 12656993, 12662034, 12672537, 12673195, 12672963, and 12669318.
Frequently Asked Questions
Do I need to do any programming myself?
No. This ECM comes fully programmed to your vehicle using the VIN you provide during checkout. It is ready for installation right out of the box, though a simple key relearn procedure may be necessary.
How do I provide my VIN?
Simply enter your 17-digit Vehicle Identification Number (VIN) in the designated field on the checkout page or send it to us in a message after your purchase. We cannot ship the module until we receive your VIN.
Is this a new or used part?
This is a high-quality, tested, and verified replacement part guaranteed to meet or exceed original equipment performance. It is flashed with new GM software for optimal operation.
What if my part number isn’t 12663391 but is on the interchange list?
If your original module’s part number is on our compatibility list, this ECM will function as a direct replacement. GM often consolidates multiple part numbers into one updated, superseding part.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the ECM (like codes P0601-P0606), then yes, this part will resolve the issue. It’s crucial to ensure other potential problems (sensors, wiring) have been ruled out first.