Is your Chevrolet, Buick, GMC, or Cadillac suffering from frustrating and hard-to-diagnose issues? An erratic idle, poor fuel economy, a persistent check engine light, or even a no-start condition can often be traced back to a failing Engine Control Module (ECM). This module, part number 12651994, is the central computer for your engine, and when it malfunctions, it can cause a cascade of problems. This replacement ECM is the definitive solution to restore your vehicle’s performance, reliability, and drivability.
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We take the guesswork and additional expense out of the equation by programming the module specifically for your vehicle using the VIN you provide. This ensures that all factory settings, security information, and performance parameters are perfectly matched to your car’s original specifications. Upon arrival, the module is ready for installation, simplifying the repair process and getting you back on the road faster.
From the Diagnostic Bay
We had a 2012 GMC Acadia come in with a P0300 random misfire code that just wouldn’t go away. The owner had already replaced all the spark plugs, ignition coils, and even the fuel injectors. The misfire was intermittent but was causing hesitation and poor mileage. After hours of chasing wires and checking sensors, we hooked up our diagnostic tools to monitor the ECM’s driver circuits for the ignition coils. We found that the driver for cylinder 3 was intermittently failing inside the module itself. We installed one of our pre-programmed ECMs, performed a quick CASE relearn, and the misfire was gone for good. It’s a classic case of a faulty internal component that no amount of external parts could fix.
Common Symptoms of a Failing Engine Computer
- ✔ Check Engine Light is on with various trouble codes (DTCs).
- ✔ Engine stalling, stumbling, or hesitating during acceleration.
- ✔ No-start condition where the engine cranks but won’t fire up.
- ✔ Poor or inconsistent fuel economy.
- ✔ Shifting problems with the automatic transmission.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Loss of spark or incorrect ignition timing.
- ✔ Inconsistent fuel injector pulse or operation.
The Critical Role of Your 2012-2013 Caprice ECM
The Electronic Control Module is the brain of your vehicle’s powertrain. It constantly analyzes data from dozens of sensors—like the oxygen sensors, crankshaft position sensor, and throttle position sensor—to make millions of calculations per second. These calculations precisely control the fuel injection, ignition timing, and transmission shift points to ensure optimal power, efficiency, and emissions. When the internal circuitry of the ECM begins to fail due to heat, vibration, or age, these critical calculations become corrupted, leading to the symptoms you’re experiencing. Replacing a faulty module with our correctly programmed unit is the only way to restore this essential function.
Plug-and-Play Solution with VIN Programming
Avoid the hassle and high cost of dealership programming. When you order from us, simply provide your vehicle’s 17-digit VIN. Our technicians will flash the module with the latest GM-certified software updates specific to your car. This ensures seamless integration with your vehicle’s other electronic systems, including the anti-theft system (Passlock/VATS). While the module is programmed for your vehicle, some models may require a simple, on-vehicle security relearn procedure which can typically be done without special tools.
Guaranteed Fitment for Multiple GM Models
This ECM, identified by part number 12651994, is a direct replacement for several other part numbers, including 12643248 and 12652814. It is designed to fit a wide array of GM vehicles. Please verify your part number and check the compatibility list below to ensure a perfect match for your car.
- ACADIA 12 (behind fan shroud)
- CAMARO 12 3.6L (ID 12643248 or 12651994)
- CAPRICE 12-13 3.6L
- CAPTIVA SPORT 12-13 (LH engine compartment, ID 12643248 or 12651994)
- CTS 12-13 3.0L or 3.6L
- CTS 14 Cpe & SW, 3.0L or 3.6L
- ENCLAVE 12 (behind fan shroud)
- EQUINOX 12 (LH engine compartment)
- IMPALA 12-13 (air cleaner bracket)
- IMPALA 14-16 VIN W (4th digit, Limited)
- LACROSSE 12 (LH engine compartment)
- MALIBU 13 2.4L (ID 12643248, 12651994, or 12652814)
- ORLANDO 12-13 (LH engine compartment, ID 12643248 or 12651994)
- REGAL 12 (LH engine compartment)
- SRX 12 (LH engine compartment)
- TERRAIN 12 (LH engine compartment)
- TRAVERSE 12 (behind fan shroud)
- VERANO 12-13
Frequently Asked Questions
Do I need to get this ECM programmed by a dealer?
No. We program the module to your vehicle’s specific VIN before shipping it to you. This handles the main software installation, so you won’t need to visit a dealership for that service.
What is a security relearn procedure?
A security relearn, sometimes called a key relearn or VATS relearn, synchronizes the new ECM with your vehicle’s existing anti-theft system. For many GM vehicles, this is a simple procedure that involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Instructions are readily available online for most models.
Where is the ECM located on my vehicle?
The location varies by model. Common locations include the left-hand (driver’s side) engine compartment, often near the air filter box (Impala, Malibu, Equinox), or behind the fan shroud (Acadia, Traverse). Always disconnect the battery before attempting to remove or install the module.
How do I provide my VIN?
You can enter your 17-digit Vehicle Identification Number (VIN) in the notes section during checkout. If you forget, we will contact you via email after your purchase to request it. We cannot ship the module until we have your VIN to program it.
Will this fix my check engine light?
If the check engine light and associated codes are caused by a faulty ECM, then yes, this part will resolve the issue. It’s crucial to properly diagnose the problem first, as other failing sensors or components can also trigger a check engine light.