Restore Peak Performance to Your GM Truck or SUV
Is your 2017 Suburban 1500 acting up? Unexplained stalling, a persistent check engine light, or a frustrating no-start condition can bring your day to a halt. As a technician with over two decades of experience under the hood, I’ve seen firsthand how a failing Engine Control Module (ECM) can cause a cascade of baffling electronic issues. This isn’t just a component; it’s the brain of your engine, and when it falters, your vehicle’s reliability is compromised. This replacement Engine Control Module, part number 12704476, is the definitive solution to get your vehicle running smoothly and dependably again.
We take the guesswork out of the repair by programming this module specifically for your vehicle using your VIN. This ensures it arrives with the latest factory software from GM, matching the exact calibration your vehicle requires for optimal fuel economy, emissions, and performance. You’re not just buying a part; you’re getting a plug-and-play-ready solution designed to restore your vehicle’s factory-level operation.
Case Study: The Intermittent No-Start Nightmare
A customer brought in a 2017 Tahoe with an issue that was driving them crazy: it would randomly refuse to start. No crank, no click. Other times, it would start perfectly. They had already replaced the battery and starter. My initial scan showed a few intermittent communication codes (U-codes), but nothing consistent. After checking the main power and ground circuits to the ECM, I noticed a slight voltage drop that shouldn’t have been there. On a hunch, I gently tapped the ECM while an assistant tried to crank the engine, and it fired right up. The culprit was an internal failure in the original module, causing a poor connection only when it felt like it. Replacing the faulty unit with a properly programmed 2017 Suburban 1500 ECM resolved the issue permanently. It’s a classic example of how ECM failure can mimic other problems.
Common Signs of a Failing ECM
- ✔ Check Engine Light is on with internal processor codes (e.g., P0601, P0606).
- ✔ Vehicle will not start or has intermittent starting issues.
- ✔ Loss of communication with the scan tool or other modules (U-codes).
- ✔ Poor engine performance, hesitation, or misfiring.
- ✔ Reduced fuel economy for no apparent reason.
- ✔ Erratic transmission shifting or failure to shift.
Your Straightforward Installation Guide
Installing your new 2017 Suburban 1500 ECM is a manageable job for a seasoned DIYer or any professional technician. Follow these steps carefully for a successful replacement.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electronic work.
- Locate the ECM: On most compatible trucks and SUVs, the ECM is found in the left-hand (driver’s side) front of the engine compartment.
- Disconnect Connectors: Carefully release the locking tabs and unplug the wiring harness connectors from the old module. 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 in place and securely fasten it.
- Reconnect Everything: Plug the wiring harnesses back into the new ECM, ensuring they click securely into place. Reconnect the negative battery terminal.
- Perform Relearn Procedures: This is a critical step. If the vehicle does not start, you must perform a Vehicle Theft Deterrent (VTD) relearn using a GM-compatible programming tool like TIS2Web or Techline Connect. Other procedures, like a crankshaft position variation relearn, may also be required.
Will This Fit My Vehicle?
This module is a direct replacement for part numbers 12692068, 12704476, 12686382, 12674052, 12674472, and 12678815. It is guaranteed to fit the following models:
- 2017 Cadillac Escalade & Escalade ESV
- 2017 Cadillac XTS (3.6L Twin Turbo LF3)
- 2017 Cadillac CTS (6.2L Supercharged or 3.6L Twin Turbo LF3)
- 2017 Cadillac ATS (3.6L Twin Turbo LF4)
- 2017 Chevrolet Corvette
- 2017 Chevrolet Tahoe
- 2017 Chevrolet Suburban 1500
- 2017-2018 Chevrolet Silverado 1500
- 2017 GMC Yukon & Yukon XL 1500
- 2017-2018 GMC Sierra 1500 & Sierra Denali 1500
- 2016 Chevrolet Silverado 1500 (ID 12674472)
- 2016 GMC Sierra 1500 (ID 12674472)
IMPORTANT: After purchasing, please provide your Vehicle Identification Number (VIN) so we can program the module with the correct, latest GM software before shipping.
Frequently Asked Questions
Why do you need my VIN?
Your VIN is essential for us to load the exact GM-specified software and calibrations for your vehicle’s engine, transmission, and options. This ensures proper function and avoids compatibility issues.
What is a “theft relearn” and can I do it myself?
The theft relearn procedure syncs the new ECM with your vehicle’s anti-theft system. It requires a professional-grade scan tool with GM programming capabilities (like Techline Connect). Most DIY mechanics do not have this tool, so this step is typically performed by a qualified repair shop.
Will this fix my check engine light?
If the check engine light is caused by an internal ECM failure (like code P0601), then yes, this part will resolve the issue. However, you should always perform a complete diagnosis to ensure the light isn’t being caused by a different faulty sensor or component.
Is this a new or used part?
This is a high-quality, tested, and verified used component that has been professionally programmed to function to OEM standards. It’s a reliable and cost-effective alternative to a new dealer part.
Do I need to do any other relearns?
Possibly. Depending on your vehicle and the original failure, additional procedures like a crankshaft position variation relearn or injector flow rate programming may be necessary for perfect idle and performance. These also require a professional scan tool.