Restore Peak Performance to Your Hummer H3
As a technician with over two decades of experience under the hood, I’ve seen firsthand the frustration that a failing Powertrain Control Module (PCM) can cause. Your 2006 Hummer H3 is a capable machine, but when its electronic brain starts to falter, you can be left chasing confusing symptoms and even get stranded. From a persistent check engine light to a vehicle that won’t start, a faulty PCM can bring your adventures to a halt. This isn’t just another part; it’s the central command for your engine’s performance, fuel economy, and emissions.
This is a direct-fit replacement 2006 Hummer H3 PCM, meticulously programmed with the latest GM-certified software updates specifically for your vehicle. We take the guesswork and the expensive trip to the dealership out of the equation. Simply provide us with your Vehicle Identification Number (VIN) during checkout, and our experts will flash the module to match your H3’s exact specifications. This ensures seamless communication between all your vehicle’s systems, restoring the reliable performance you depend on.
From the Diagnostic Bay: The Intermittent Gremlin
I remember a 2006 Chevy Colorado—which uses this same family of PCM—that came into my shop with a problem that was driving the owner crazy. It would run perfectly for days, then suddenly start shifting hard and lose power. No consistent codes, just a random U0100 (Lost Communication with ECM/PCM). We checked wiring, grounds, and connectors for hours. On a hunch, I tapped the PCM with a screwdriver handle while the engine was running, and the truck immediately stalled. The culprit was an internal solder joint failure inside the module, a common issue caused by years of heat cycles and vibration. A pre-programmed replacement like this one had the truck running reliably in under an hour, saving the customer from replacing a perfectly good transmission.
Is Your H3 Showing These Telltale Signs?
- ✔ Persistent Check Engine Light (CEL) that won’t clear
- ✔ Engine cranks but refuses to start
- ✔ Rough or unstable idle
- ✔ Noticeable decrease in fuel economy
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Communication error codes, such as P0601, P0606, or U0100
- ✔ Stalling for no apparent reason
A Straightforward Guide to Installation
Installing your new 2006 Hummer H3 PCM is a job most DIYers can handle with basic tools. The module is typically located on the right-hand (passenger side) firewall.
- Safety First: Disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes to allow the system to fully discharge.
- Locate the PCM: On your Hummer H3, find the PCM mounted to the firewall on the passenger side of the engine bay.
- Disconnect Wiring: Carefully release the locking tabs on the electrical connectors and unplug them from the old module. Avoid forcing them.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. Keep the hardware as you will reuse it.
- Install the New Module: Mount your new, pre-programmed PCM onto the bracket and secure it with the original hardware.
- Reconnect Everything: Plug the wiring harnesses back into the new module until they click securely in place. Reconnect the negative battery terminal.
- Perform Security Relearn: You will need to perform a simple key-cycle security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds, and repeating this process three times. Your vehicle’s service manual will have the exact steps. This syncs the new PCM with your vehicle’s anti-theft system.
Verified Vehicle Compatibility List
This module is a direct replacement for a wide range of GM vehicles and part numbers. Please verify your model and part number below. This unit is compatible with service numbers: 12569773, 12588650, 12589311, 12589585, 12591647, 12591648, 12593531, 12593532, 12594430, 12594431, 12596783, 12596784, 12597521, 12597776, 12597777, 12600818, 12604438, 12604439, 12606369, 12606373, 12606374, 12606398, 12606399, 19209820, and 19209821.
- HUMMER H3 2006 (RH firewall)
- CHEVROLET COLORADO 2004-2006 (RH firewall)
- GMC CANYON 2004-2006 (RH firewall)
- CHEVROLET TRAILBLAZER & TRAILBLAZER EXT 2006 (4.2L, LH engine)
- GMC ENVOY & ENVOY XL 2006 (4.2L, LH engine)
- BUICK RAINIER 2006 (4.2L, LH engine)
- ISUZU ASCENDER 2006 (4.2L, LH engine)
- ISUZU I-280 2006 (RH firewall)
- ISUZU I-350 2006 (RH firewall)
- SAAB 9-7X 2006 (6 cylinder)
Why do you need my VIN?
Why do you need my VIN?
Your VIN is essential for us to program the Powertrain Control Module correctly. It allows us to load the exact GM-approved software for your Hummer’s specific options, engine, transmission, and emissions equipment. This ensures a true plug-and-play installation without needing a trip to the dealer.
Is this a difficult part to install myself?
Not at all. For most DIYers with basic hand tools, this is a straightforward job that can be done in under an hour. The main steps are disconnecting the battery, swapping the module, and performing a simple key-cycle security relearn procedure. Our guide above outlines the process.
Will I need any other programming or special tools?
No. Because we program the module to your VIN before shipping, you will not need any expensive scan tools or dealer-level software. The only post-installation procedure required is the security relearn, which is done with your vehicle’s ignition key.
What is a security relearn procedure?
The security relearn, or anti-theft relearn, is a simple process that syncs the new PCM to your vehicle’s existing keys and security system. It typically involves a sequence of turning the key on and off for set periods. This tells your vehicle that the new computer is an authorized component, allowing the engine to start and run.