Is your 2017 Chevrolet Caprice or other GM vehicle suddenly stalling, running rough, or refusing to start? A frustrating and often misdiagnosed check engine light can point directly to a failing Engine Control Module (ECM). As a technician with over 20 years of experience, I’ve seen firsthand how a faulty ECM can cripple a perfectly good engine. This isn’t just a part; it’s the central command center for your vehicle’s performance and fuel economy. When it fails, you need a reliable, direct-fit solution that gets you back on the road without the hassle and expense of a dealership visit.
This ECM, part number 12667189, is the definitive solution. We take the guesswork out of the repair by programming the module specifically to your vehicle’s VIN before it ships. This means it arrives at your door with the latest GM software updates already installed, ready for a straightforward installation. You get a component that restores original performance and communication between all your vehicle’s critical systems.
Diagnosing a Faulty Engine Computer
If you’re experiencing any of the following issues, a failing ECM is a likely culprit. I’ve diagnosed hundreds of these, and the symptoms are often consistent across the GM platform.
- ✔ Check Engine Light is on with communication-related Diagnostic Trouble Codes (DTCs) such as P0601, P0606, or U0100.
- ✔ The engine cranks but refuses to start for no apparent reason.
- ✔ Intermittent stalling, especially after the vehicle has warmed up.
- ✔ Noticeable decrease in fuel efficiency and overall engine performance.
- ✔ Transmission shifting issues or erratic behavior.
- ✔ Communication problems with your scan tool.
From the Diagnostic Bay
I remember a 2017 Cadillac XTS with the 3.6L engine that came into my shop on a tow truck. The owner was frustrated; he’d already replaced the battery and alternator, but the car would randomly die and refuse to restart for hours. My scan tool couldn’t consistently communicate with the ECM. After checking the power and ground circuits to the module, which were solid, I knew the internal processor was failing. Instead of a costly trip to the dealer, we ordered a VIN-programmed ECM. The installation and security relearn took less than 30 minutes in his driveway. The car fired right up and has run flawlessly since. This is the exact, reliable fix we offer here.
A Straightforward Guide to Installation
Installing your pre-programmed 2017 Caprice ECM is a manageable job for a DIY enthusiast or any professional mechanic. Following these steps ensures a smooth process.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the ECM: The location varies by model (e.g., behind the fan shroud on a Traverse, LH engine compartment on an Equinox). Consult a repair guide for your specific vehicle if you’re unsure.
- Disconnect and Remove: Carefully unplug the wiring harness connectors. They have locking tabs that need to be released. Then, unbolt the old ECM from its mounting bracket.
- Install the New ECM: Mount the new module securely in place and reconnect the wiring harnesses. Ensure they click into place to confirm a solid connection.
- Reconnect Battery: Reattach the negative battery terminal.
- Perform Security Relearn: You will need to perform a security relearn procedure (often called a ‘key relearn’ or ‘anti-theft relearn’). This simple process typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. This allows your vehicle’s anti-theft system to recognize the new ECM.
Verified Vehicle Compatibility
This module is a direct replacement for part numbers 12667002, 12666070, and 12667189. It is guaranteed to fit the following models and configurations:
- ✔ 2017 Chevrolet Caprice (with 3.6L engine)
- ✔ 2017 Chevrolet Traverse (located behind fan shroud)
- ✔ 2017-2019 Cadillac XTS (with 3.6L LFX engine, VIN 3)
- ✔ 2017 GMC Acadia (Limited models, VIN J)
- ✔ 2017 Buick Enclave (located behind fan shroud)
- ✔ 2017 Buick Regal (located in LH engine compartment)
- ✔ 2017 Buick Verano
- ✔ 2017-2019 Chevrolet Impala
- ✔ 2017 Chevrolet Equinox (located in LH engine compartment)
- ✔ 2017 GMC Terrain (located in LH engine compartment)
Frequently Asked Questions
2017 Caprice ECM
Do I need to do anything after I buy it?
Yes. After your purchase, you must send us your vehicle’s 17-digit VIN. We cannot program and ship your until we receive this information.