Restore Peak Performance to Your HUMMER H3
If you’re dealing with frustrating engine problems in your 2009-2010 HUMMER H3—like erratic idling, sudden stalling, a persistent Check Engine Light, or a complete no-start situation—a failing Engine Control Module (ECM) is a very likely culprit. As a technician with over two decades of experience, I’ve seen how a faulty ECM can turn a reliable vehicle into a source of constant headaches. This isn’t just a component; it’s the brain of your engine, and when it falters, everything from fuel delivery to ignition timing is compromised.
This replacement Engine Control Module is the definitive solution. We take the guesswork and high costs out of the repair by pre-programming the unit specifically for your vehicle using your VIN. This means it arrives at your door with the latest GM factory software updates already installed, ready for a straightforward installation. You get a reliable, fully functional module without the need for an expensive trip to the dealership for programming.
Case Study: A Tricky Diagnosis
I remember a 2009 H3 that came into the shop with an intermittent stalling problem that was driving the owner crazy. It would run fine for days, then suddenly die at a stoplight. No other shop could pinpoint the issue because no hard fault codes were being stored—just a few random communication errors. After checking all the usual suspects like the fuel pump and crank sensor, my diagnostic process led me to the ECM. On the surface, it seemed fine, but under load and after heating up, the processor would drop communication packets, causing the engine to shut down. Swapping in a properly programmed ECM like this one solved the problem instantly. It’s a classic example of how ECM failure can mimic other issues, making a quality-tested part essential.
Is Your H3 Showing These Symptoms?
A failing ECM can manifest in numerous ways. If you’re experiencing any of the following, this module is your likely solution:
- ✔ Unexplained Check Engine Light (CEL) illumination
- ✔ Stored diagnostic trouble codes (DTCs) like P0601, P0606, or U0100
- ✔ Engine stalling or shutting off while driving
- ✔ Complete no-start condition where the engine cranks but won’t fire
- ✔ Noticeable decrease in fuel economy
- ✔ Poor engine performance, hesitation, or misfires
- ✔ Transmission shifting issues or erratic behavior
A Straightforward Guide to Installation
One of the biggest benefits of this module is its ease of installation. For the confident DIYer or professional mechanic, this is a job you can complete with basic hand tools. Here’s a general guide:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electrical work.
- Locate the ECM: On the 2009-2010 HUMMER H3, the ECM is located on the passenger side (RH) of the engine bay, mounted to the firewall.
- Disconnect the Module: Carefully release the locking tabs on the electrical connectors and pull them straight out. Avoid wiggling them side-to-side to prevent pin damage.
- Remove the Old Unit: Unbolt the old ECM from its mounting bracket on the firewall.
- Install the New Module: Mount your new, pre-programmed ECM in place and securely tighten the bolts.
- Reconnect Everything: Firmly plug the electrical connectors back into the new module until they click into place. Reconnect the negative battery terminal.
- Final Steps: In some cases, a security relearn procedure may be required. This can typically be done by cycling the key and is a simple process you can find in your owner’s manual or online.
Verified Vehicle Compatibility
While this is the primary solution for the 2009-2010 HUMMER H3 ECM, this module, service number 12630464, is also a direct replacement for a wide range of GM vehicles. It is interchangeable with part numbers 12636659, 12639300, 1263605, 12628993, 12628911, 12625453, 12622175, and 12678512. Please verify your vehicle and options below:
COLORADO 09-12 (2.9L, 3.7L)
CORVETTE 09 (ZR1)
CTS 09 (6.2L)
DTS 09-11
ENVOY 09 (5.3L)
HUMMER H3 09-10
LUCERNE 09-11 (4.6L)
SAAB 9-7X 09
SRX 09 (4.6L)
STS 09-10 (4.4L, 4.6L)
TRAILBLAZER 09 (6.0L)
XLR 09
Frequently Asked Questions
Do I need to get this ECM programmed by a dealer?
No. We handle all the programming for you before shipment. Just provide us with your vehicle’s 17-digit VIN during checkout, and it will arrive ready to install with the latest GM software.
Where is the ECM located on my 2009 HUMMER H3?
The Engine Control Module is mounted to the firewall on the right-hand (passenger) side of the engine compartment.
What information do you need from me to program the module?
We need your vehicle’s complete 17-digit Vehicle Identification Number (VIN). This ensures we load the exact software and calibrations for your H3’s specific options.
Will this fix my specific problem or Check Engine Light code?
This module will resolve issues directly caused by a faulty ECM. If your diagnostic trouble codes (like P0601 – Internal Control Module Memory Check Sum Error) point to an internal computer failure, this part is the correct fix.
Is this a simple plug-and-play installation?
Yes, for the most part. After the physical installation, some GM vehicles require a security relearn procedure, which typically involves cycling the ignition key. This procedure does not require special tools.