Is your HUMMER H2 or GM truck running rough, stalling unexpectedly, or showing a stubborn Check Engine Light? As a technician with over two decades of experience, I’ve seen these symptoms countless times. Often, the root cause isn’t a sensor or a mechanical part, but the vehicle’s central computer—the Powertrain Control Module (PCM). This module is the brain of your engine and transmission, and when it fails, it can cause a wide range of frustrating and hard-to-diagnose problems.
This isn’t just a replacement part; it’s a complete solution. We are offering a reliable Powertrain Control Module, part number 12602802, that comes fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We flash it with the latest, most stable software updates directly from GM. This critical step ensures your vehicle operates exactly as the manufacturer intended, often correcting factory bugs that you may not have even known were affecting your fuel economy and performance. Forget about expensive towing fees and dealership programming costs. This module arrives at your door ready for a straightforward installation.
From the Diagnostic Bay: The Intermittent Stall Case
I remember a 2006 Hummer H2 that came into the shop with an issue that had stumped two other mechanics. The owner said it would randomly stall at stoplights, but never set a consistent trouble code. We checked fuel pressure, ignition components, and wiring harnesses—all perfect. On a hunch, I monitored the live data stream from the PCM and noticed momentary data dropouts right before a stall. The original PCM was failing internally under specific thermal conditions. We installed a VIN-programmed module just like this one, performed the security relearn, and the problem was gone for good. It’s a classic example of how a failing PCM can mimic other, more common issues.
Is Your Truck Showing These Telltale Signs?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, your engine computer is a likely culprit:
- âś” Unexplained Check Engine Light (CEL)
- âś” Engine stalling, stuttering, or misfiring
- âś” No-start or hard-starting conditions
- âś” Poor or inconsistent automatic transmission shifting
- âś” Noticeable decrease in fuel efficiency
- âś” Communication error codes, such as U0100
- âś” Internal module failure codes, like P0601 or P0606
Your Straightforward PCM Installation Guide
Replacing the 2003-2007 HUMMER H2 PCM is a job most DIYers can handle. The module is typically located in the engine bay on the driver’s side, under or near the battery. Always consult a vehicle-specific repair manual, but here are the general steps:
- Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post.
- Locate the PCM: Find the module in the engine bay. On the H2 and many compatible GM trucks, it’s under the battery tray. You may need to remove the battery to access it.
- Disconnect Connectors: Carefully unplug the wiring harness connectors from the old PCM. These usually have locking tabs that need to be released. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the PCM from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed PCM into place and securely reconnect the wiring harnesses. Ensure they click into place.
- Reconnect Battery: Reinstall the battery (if removed) and reconnect the negative battery terminal.
- Perform Security Relearn: You will need to perform a simple security relearn procedure (often called a CASE relearn or anti-theft relearn). This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. This allows your vehicle’s anti-theft system to recognize the new PCM.
Verified Compatibility for Your GM Truck or SUV
This module, part number 12602802, is a direct replacement for service numbers 89017750, 12582605, 12589463, 89017734, and 28042802. It fits a wide range of General Motors vehicles. Please verify your part number or contact us with your VIN to confirm fitment. This is a partial list of compatible models:
- HUMMER H2: 2003, 2004, 2005, 2006, 2007
- Cadillac Escalade, ESV, EXT: 2003-2006
- Chevrolet Avalanche 1500: 2003-2006
- Chevrolet Silverado 1500, 2500, 3500: 2003-2007 (Classic body style for ’07)
- Chevrolet Suburban 1500, 2500: 2003-2006
- Chevrolet Tahoe: 2003-2006
- GMC Sierra 1500, 2500, 3500: 2003-2007 (Classic body style for ’07)
- GMC Yukon, Yukon XL 1500, Yukon XL 2500: 2003-2006
- Chevrolet SSR: 2003
- And more…
Why do you need my VIN?
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential. It allows us to program the PCM with the exact software calibration and updates specific to your vehicle’s engine, transmission, and factory options. This ensures perfect compatibility and optimal performance, eliminating the need for a trip to the dealer.
Is this a plug-and-play part?
Almost! Because it arrives pre-programmed to your VIN, the complex part is done. The only remaining step after physical installation is a simple ‘security relearn’ procedure. This takes about 30 minutes and can be done by anyone with just the vehicle’s key—no special tools are required.
Will this fix my specific problem?
This 2003-2007 HUMMER H2 PCM is a direct solution for issues caused by a faulty module, such as internal processor errors (P0601-P0606), communication loss, and other symptoms listed above. If your vehicle has been properly diagnosed with a bad PCM, this part is the correct fix.
Do I need to return my old PCM (core)?
Please check the specific terms of this listing. Typically, a core return is not required, but policies can vary. This allows you to get your vehicle running without the pressure of immediately shipping a part back.