Is Your GM Truck Running Rough? It Could Be The PCM.
If your 2003-2006 Avalanche 1500, or another compatible GM truck or SUV, is experiencing frustrating issues like a persistent check engine light, erratic shifting, a no-start condition, or poor fuel economy, a failing Powertrain Control Module (PCM) is a very likely culprit. As the central computer for your engine and transmission, when the PCM starts to fail, it can cause a cascade of problems that are often difficult to diagnose. You’re not just buying a part; you’re buying a solution to get your reliable truck back on the road.
From the Shop Floor: A Real-World Scenario
“A customer’s 2005 Silverado 1500, which uses this exact same PCM, came into my shop last month. It had a random no-start problem and the transmission would sometimes refuse to shift out of first gear. The owner had already replaced the battery and alternator, but the issues continued. After hooking up my scanner, I saw communication loss codes with the PCM. A quick check of the main ground wire under the driver’s door showed it was clean and tight. The problem was internal to the module itself. We installed one of these VIN-programmed PCMs, performed the security relearn, and the truck has been running perfectly ever since. Itโs a common failure point I’ve seen hundreds of times on these otherwise bulletproof trucks.”
The Plug-and-Play Solution for Your 2003-2006 Avalanche 1500 PCM
Don’t waste time and money at a dealership. We make this repair straightforward. This replacement PCM, part number 12582605, is professionally programmed with the latest GM-certified software specifically for your vehicle’s Vehicle Identification Number (VIN). This critical step ensures that the module communicates perfectly with your truck’s specific engine, transmission, and options package right out of the box.
Common Symptoms of a Failing PCM:
- โ Persistent Check Engine Light (CEL)
- โ Vehicle won’t start or starts intermittently
- โ Harsh or erratic automatic transmission shifting
- โ Decreased fuel mileage
- โ Engine stalling, stuttering, or misfiring
- โ Communication errors with diagnostic scan tools
Simple Installation: Get Back on the Road Fast
Installing your new PCM is a job most DIY mechanics can handle in under an hour with basic tools. While the final step requires a security relearn procedure (which can be done without a scan tool), the physical swap is simple.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: On most compatible trucks like the Avalanche, Silverado, and Sierra, the PCM is located in the engine bay on the driver’s side, under or next to the battery tray.
- Disconnect the Connectors: Carefully unclip and remove the electrical wiring harnesses from the old PCM. Inspect the connectors for any signs of corrosion or damage and clean them if necessary.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New PCM: Mount your new, pre-programmed PCM, reconnect the wiring harnesses, and re-secure the battery terminal.
- Perform Security Relearn: You will need to perform a GM security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating this cycle three times. This allows the new PCM to sync with your vehicle’s anti-theft system.
Guaranteed Compatibility
This module is a direct replacement for service numbers 89017750, 12582605, 12589463, 12602802, 89017734, and 28042802. It fits a wide range of GM trucks and SUVs, including many Chevrolet Silverado, GMC Sierra, Tahoe, Yukon, Suburban, Cadillac Escalade, and Hummer H2 models from 2003-2007. Please use the fitment chart to confirm compatibility with your exact year, make, and model.
IMPORTANT: After purchase, please send us your 17-digit VIN. We cannot ship your order until we have programmed the module. This ensures you receive a part that is 100% ready for your vehicle.