Restore Peak Performance to Your Hummer H3
Is your 2009-2010 Hummer H3 suffering from frustrating issues like intermittent stalling, a persistent check engine light, or a complete no-start condition? Before you spend a fortune at the dealership, consider the root cause: a failing Engine Control Module (ECM). As the brain of your vehicle’s engine, the ECM governs everything from fuel mixture and ignition timing to transmission shifting. When it fails, the symptoms can be unpredictable and maddening. This is the reliable, cost-effective solution you’ve been searching for.
This isn’t just a replacement part; it’s a complete fix. We take the hassle and expense out of the equation by programming this ECM specifically for your vehicle using your VIN. It arrives at your door with the latest GM software updates already installed, making it a true plug-and-play component. You get restored performance and reliability without the need for expensive scan tools or a trip to the dealer for programming.
Is Your H3 Showing These Telltale Signs?
- ✔ Unexplained check engine light with codes like P0601, P0606, or other internal processor faults.
- ✔ The engine cranks but refuses to start.
- ✔ Stalling for no reason, either at idle or while driving.
- ✔ Noticeably poor fuel economy and sluggish acceleration.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Communication errors with other modules on the vehicle (U-codes).
- ✔ Failure to pass an emissions or smog test.
From the Diagnostic Bay: The Ghost in the Machine
I remember a 2009 Hummer H3 that came into my shop after visiting two other garages. The owner was frustrated with an intermittent no-start problem that nobody could pin down. It would start fine for a week, then leave him stranded. The battery, starter, and fuel pump had all been replaced. After connecting my scope, I noticed the injector pulse and ignition coil commands were dropping out randomly. On a hunch, I used a heat gun on the ECM, and sure enough, the engine stalled and wouldn’t restart until the module cooled down. A new, properly programmed ECM like this one solved the problem permanently. These internal failures are common and can be a nightmare to diagnose without experience.
Your Straightforward Installation Guide
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post.
- ✔ Locate the ECM: On the Hummer H3, the ECM is typically located on the right-hand (passenger) side of the firewall in the engine bay.
- ✔ Disconnect the Harnesses: Carefully release the locking tabs on the electrical connectors and pull them straight out from the module. Avoid pulling on the wires themselves.
- ✔ Remove the Old Module: Unbolt the old ECM from its mounting bracket. There are usually a few bolts holding it in place.
- ✔ Install the New ECM: Mount your new, pre-programmed ECM onto the bracket and securely tighten the bolts.
- ✔ Reconnect Everything: Plug the electrical harnesses back into the new module until they click firmly into place. Reconnect the negative battery terminal.
- ✔ Perform Security Relearn: You will need to perform a simple key-cycle security relearn procedure. We include easy-to-follow instructions for this step with your order. This takes about 30 minutes and requires no special tools.
Verified Vehicle Compatibility List
This ECM is a direct replacement for a wide range of GM vehicles. While this is a 2009-2010 Hummer H3 ECM, it also fits the following models. Please verify your specific application.
- Buick DTS: 2009-2011
- Buick Lucerne: 2009-2011 (4.6L)
- Cadillac CTS: 2009 (6.2L)
- Cadillac SRX: 2009 (4.6L)
- Cadillac STS: 2009 (4.4L, 4.6L), 2010 (4.6L)
- Cadillac XLR: 2009
- Chevrolet Colorado: 2009, 2010-2012 (2.9L, 3.7L)
- Chevrolet Corvette: 2009 (ZR1)
- Chevrolet Trailblazer: 2009 (6.0L)
- GMC Canyon: 2009, 2010-2012 (2.9L, 3.7L)
- GMC Envoy: 2009 (5.3L)
- Hummer H3: 2009-2010
- Saab 9-7x: 2009
This module is interchangeable with the following service numbers: 12636659, 12639300, 1263605, 12628993, 12628911, 12625453, 12622175, 12630464, 12678512.
Frequently Asked Questions
How does the VIN programming work?
After you place your order, you simply provide us with your vehicle’s 17-digit VIN. We use official GM equipment to load the correct software and calibration files for your specific vehicle onto the module before we ship it.
Do I need to take my vehicle to a dealer after installation?
No. Because this module comes pre-programmed, you do not need a trip to the dealer. The only step required after installation is a simple security relearn procedure, which you can do yourself in your driveway with just the key. Instructions are included.
Is this a difficult part for a DIY mechanic to install?
Not at all. The physical swap is very straightforward, typically involving just a few bolts and electrical connectors. The included instructions for the security relearn make it a job most DIYers can complete with basic hand tools in under an hour.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the ECM (common codes P0601-P0606), then yes, this will resolve the issue. However, if the light is on for another reason (like a bad oxygen sensor), you will still need to fix that separate problem.
What information do I need to provide when I order?
We only need your vehicle’s VIN (Vehicle Identification Number) to ensure we program the module with the exact software for your truck’s engine, transmission, and options.