Restore Peak Performance to Your Hummer H3
Is your 2009-2010 Hummer H3 suffering from frustrating issues like a persistent check engine light, erratic idling, stalling, or a complete no-start condition? These are classic signs that the brain of your engine—the Engine Control Module (ECM)—is failing. As a technician with over two decades of experience, I’ve seen how a faulty ECM can cause a cascade of problems that are often misdiagnosed. This isn’t just an inconvenience; it’s a reliability issue that can leave you stranded. Our professionally prepared ECM is the definitive solution, arriving at your door programmed to your vehicle’s specific VIN with the latest GM software updates.
Case Study: A Tricky Diagnosis
A customer brought in a 2009 H3 that would randomly stall at traffic lights. No codes were stored initially, making it a diagnostic headache. We checked fuel pressure, sensors, and wiring, but everything seemed fine. On a long test drive, the check engine light finally flickered on, and we pulled a P0606 (ECM/PCM Processor Fault) code. The internal processor was failing intermittently under heat soak. Instead of a costly, multi-day repair at the dealer, we installed one of our VIN-programmed modules. The entire job took less than an hour, and the H3 has been running flawlessly ever since. This is the kind of straightforward, effective fix we provide.
Is Your Hummer H3 Showing These Symptoms?
- ✔ Persistent Check Engine Light (CEL) that won’t clear.
- ✔ Diagnostic Trouble Codes (DTCs) related to internal module failure, such as P0601, P0602, or P0606.
- ✔ Communication errors with other modules, often indicated by U-codes (e.g., U0100).
- ✔ Unexplained drop in fuel economy.
- ✔ Rough or unstable engine idle.
- ✔ Engine stalling, hesitation, or complete failure to start.
- ✔ Apparent transmission shifting problems that aren’t related to the transmission itself.
A Straightforward Guide to Installation
Replacing the 2009-2010 Hummer H3 ECM is a job most DIYers can handle. Our pre-programming service eliminates the need for expensive dealership tools.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the ECM: On the Hummer H3, the ECM is typically mounted to the firewall on the right-hand (passenger) side of the engine bay.
- Disconnect Connectors: Carefully release the locking tabs and unplug the electrical wiring harnesses from the old module. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the mounting hardware holding the old ECM in place and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed ECM in the same location and secure it with the original hardware.
- Reconnect Everything: Plug the wiring harnesses firmly back into the new module until they click. Reconnect the negative battery terminal.
- Perform Security Relearn: You may need to perform a simple security relearn procedure (often called Passlock or Passkey) to sync the new ECM with your vehicle’s anti-theft system. This typically involves turning the key to the ‘ON’ position for 10-15 minutes.
Verified Vehicle Compatibility
This module, part number 12630464, is a direct replacement for a wide range of GM vehicles. It is interchangeable with service numbers 12636659, 12639300, 1263605, 12628993, 12628911, 12625453, 12622175, and 12678512. Please verify your vehicle is on the list below. Upon purchase, we require your VIN to ensure perfect programming.
CADILLAC CTS 09 Electronic Control Module; 6.2L
CADILLAC DTS 09-11 Electronic Control Module
CADILLAC SRX 09 Electronic Control Module; 4.6L
CADILLAC STS 09 Electronic Control Module; 4.4L or 4.6L
CADILLAC STS 10 Electronic Control Module; 4.6L
CADILLAC XLR 09 Electronic Control Module; ID 12625453 or 12636659
CHEVROLET COLORADO 09-12 Electronic Control Module
CHEVROLET CORVETTE 09 Electronic Control Module; ZR1
CHEVROLET TRAILBLAZER 09 Electronic Control Module; 6.0L
GMC CANYON 09-12 Electronic Control Module
GMC ENVOY 09 Electronic Control Module; 5.3L
BUICK LUCERNE 09-11 Electronic Control Module; 4.6L
SAAB 9-7X 09 Electronic Control Module
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential. It allows us to access the exact factory software for your Hummer H3’s specific configuration, including engine, transmission, and emissions options. This ensures the module works perfectly right out of the box.
Is any additional programming needed after installation?
No dealership programming is required. The module arrives fully programmed. However, you will likely need to perform a simple ‘security relearn’ procedure at home, which takes about 10-15 minutes and allows the new ECM to sync with your vehicle’s anti-theft system. Instructions are readily available online for your model.
Will this fix my check engine light?
If the check engine light is caused by an internal ECM failure (like codes P0601-P0606), then yes, this part will resolve the issue. It’s crucial to properly diagnose the problem first, as the light can be triggered by many other failing components, like sensors or wiring.
Is this a brand new part?
This is a high-quality, tested, and verified original equipment part that has been professionally prepared for your vehicle. Each unit is inspected and programmed to strict standards to ensure reliability and performance equivalent to a new component.
What is the warranty on this module?
We stand behind our work. This ECM comes with a comprehensive warranty that covers any defects in the module or the programming. Please see our warranty page for full details and duration.