Programmed 2014-2016 ATS ECM 12662034 | Engine Control Module for GM

Restore Peak Performance to Your GM Vehicle

Is your Cadillac, Silverado, or Corvette suffering from frustrating issues like stalling, erratic shifting, a persistent check engine light, or a complete no-start condition? As a technician with over two decades of diagnostic experience, I’ve seen these symptoms countless times. More often than not, the root cause is a failing Engine Control Module (ECM)—the computer that serves as your vehicle’s brain. When it falters, it can throw your engine’s entire operation into chaos, leading to poor fuel economy and unreliable performance. This isn’t just an inconvenience; it’s a problem that needs a dependable solution.

This replacement ECM, part number 12662034, is the definitive fix for a wide range of popular GM vehicles. What sets this module apart is our professional programming service. Before we ship it, we flash the module with the latest, most stable software updates directly from GM, tailored specifically to your vehicle using its VIN. This means you get a component that’s not just a replacement, but a solution that incorporates years of factory improvements for drivability and efficiency. You’re getting a part that is ready for installation right out of the box, eliminating the need for expensive dealership programming or specialized scan tools.

Is Your Vehicle Showing These Signs of ECM Failure?

A failing ECM can manifest in various ways, often mimicking other component failures. If you’re experiencing any of the following, a faulty module is a likely culprit. In my shop, I always check for these tell-tale signs and associated Diagnostic Trouble Codes (DTCs):

• ✔ Engine stalling or misfiring for no apparent reason
• ✔ Complete no-start condition where the engine cranks but won’t fire
• ✔ A persistent Check Engine Light (CEL) that won’t clear
• ✔ Common trouble codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault)
• ✔ Noticeable decrease in fuel efficiency
• ✔ Harsh or incorrect automatic transmission shifting
• ✔ Communication errors with other vehicle modules (U-codes)

A Straightforward Guide to Your ECM Installation

Installing your new ECM is a manageable job for a confident DIYer or any professional mechanic. By having us program it beforehand, you’ve already handled the most complex part of the job. Follow these general steps for a smooth installation:

1. Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental reconnection.
2. Locate the ECM: On most of these GM vehicles (like the Silverado/Sierra and Escalade), the ECM is located in the engine compartment, typically on the driver’s side front. On others, like the Corvette, it may be under the cowl. Consult a vehicle-specific repair guide if you’re unsure.
3. Disconnect the Connectors: Carefully release the locking tabs on the electrical wiring harnesses and gently pull them straight out from the module. Never force them. Inspect the pins for any corrosion or damage.
4. Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware, as you will need it to install the new one.
5. Install the New ECM: Mount your new, pre-programmed ECM onto the bracket and secure it with the original hardware. Reconnect the wiring harnesses, ensuring they click securely into place.
6. Reconnect the Battery: Reattach the negative battery terminal.
7. Perform Security Relearn: Even with programming, most GM vehicles require a simple security relearn procedure to sync the new ECM with the anti-theft system. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. Your vehicle should then start.

Verified Compatibility for Your GM Vehicle

This module is a direct replacement for several part numbers and fits a wide array of GM cars, trucks, and SUVs. Please verify your vehicle is on this list. It is crucial to provide your VIN upon purchase to ensure we load the correct software for your specific model, year, and options.

Frequently Asked Questions