Restore Peak Performance to Your HUMMER H2
Is your 2003-2007 HUMMER H2 suffering from baffling electrical issues, poor engine performance, or a persistent check engine light? The Powertrain Control Module (PCM), often called the Engine Control Module (ECM), is the central computer of your vehicle. It meticulously manages everything from fuel injection and ignition timing to transmission shifting and emissions control. When it begins to fail, it can cause a cascade of frustrating and difficult-to-diagnose problems. This replacement PCM, part number 12582605, is the definitive solution to restore your vehicle’s factory performance and reliability.
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We take the guesswork and additional expense out of the repair process. Upon purchase, simply provide us with your vehicle’s VIN. Our technicians will then program the module with the latest, most stable software updates directly from GM. This ensures perfect compatibility and optimal performance for your specific vehicle configuration, eliminating the need for a costly trip to the dealership for programming.
From the Diagnostic Bay
We had a 2005 HUMMER H2 come into the shop with a complaint of harsh, erratic shifting and a check engine light for a transmission solenoid code. The owner had already replaced the solenoid pack twice with no change. After confirming the transmission wiring was intact, we suspected the driver circuit inside the PCM. Instead of chasing ghosts further, we installed a VIN-programmed PCM. On the first test drive, the shifting was buttery smooth, and the code never returned. It’s a classic case of a failing computer mimicking a mechanical fault, costing the owner time and money on unnecessary parts before finding the true root cause.
Is Your HUMMER H2 PCM Failing?
A faulty Powertrain Control Module can manifest in numerous ways, often mimicking other component failures. If you’re experiencing any of the following symptoms, a failing PCM could be the culprit. This replacement module is designed to resolve these common issues and get you back on the road with confidence.
- ✔ Check Engine Light: The check engine light is illuminated, often with communication-related (U-codes) or processor fault codes (P06xx codes).
- ✔ Erratic Shifting: Your automatic transmission may shift harshly, slip between gears, or get stuck in one gear (limp mode).
- ✔ Poor Fuel Economy: A sudden and unexplained drop in MPG can be caused by the PCM failing to properly calculate the air-fuel mixture.
- ✔ Engine Stalling or Misfiring: The engine may stall intermittently, misfire, or run rough, as the PCM struggles to control spark and fuel delivery.
- ✔ No-Start Condition: In severe cases, the vehicle may crank but fail to start because the PCM is not activating the fuel pump or ignition coils.
- ✔ Failed Emissions Test: An inability to pass an emissions test is a common sign of a PCM that can no longer properly manage the vehicle’s emissions systems.
- ✔ Communication Issues: Your mechanic’s scan tool may be unable to communicate with the PCM, indicating a total failure.
A True Plug-and-Play Solution
Replacing a PCM used to be a complicated job requiring specialized tools and dealer intervention. Our process simplifies this repair. By programming the module to your specific VIN before shipping, we handle the most critical step for you. When the part arrives, the installation is straightforward for a DIY mechanic or any professional technician. In most cases, after installation, you may only need to perform a simple security relearn procedure, which can often be done without any special tools. This module is a direct replacement for service numbers 89017750, 12582605, 12589463, 12602802, 89017734, and 28042802, ensuring broad compatibility across a wide range of GM trucks and SUVs from this era.
Frequently Asked Questions
Do I need to get this PCM programmed?
No. This module comes fully programmed to your vehicle’s specific VIN. Simply provide your VIN at checkout, and we handle the programming before it ships, saving you a trip to the dealer.
Where is the PCM located on my 2003-2007 HUMMER H2?
The PCM is typically located in the engine bay, on the driver’s side (LH) front, underneath the battery tray. You will need to remove the battery to access it.
What is a VIN and why is it required?
The VIN (Vehicle Identification Number) is a unique 17-digit code for your vehicle. We use it to load the exact factory software and calibrations for your HUMMER’s specific engine, transmission, and options, ensuring perfect functionality.
Will this fix my check engine light?
If the check engine light is caused by an internal fault within the original PCM, then yes, this replacement part will solve the issue. It’s crucial to properly diagnose the codes to ensure the PCM is the root cause.
Is any additional setup required after installation?
In some cases, a security relearn procedure (also known as a Passlock relearn) may be necessary for the vehicle to start. This procedure can typically be done without special tools and instructions are widely available online. A crankshaft position sensor variation relearn (CASE relearn) may also be needed with a capable scan tool to prevent a P0315 code.