Is Your GM Truck or SUV Running Rough?
If you’re dealing with a frustrating check engine light, erratic transmission shifting, a no-start condition, or poor fuel economy, a failing Powertrain Control Module (PCM) is often the culprit. As a mechanic with over 20 years of experience, I’ve seen these symptoms countless times on otherwise solid trucks. The PCM is the brain of your vehicle’s engine and transmission, and when it starts to fail, it can cause a cascade of problems that are difficult to diagnose. This isn’t just an inconvenience; it’s a reliability issue that can leave you stranded.
The Direct-Fit, Programmed Solution
This isn’t just a replacement part; it’s a complete solution. We take a genuine OEM PCM, part number 12602802, and professionally program it to your vehicle’s specific Vehicle Identification Number (VIN). This means it arrives at your door loaded with the latest GM factory software updates, ensuring optimal performance and compatibility. You get a part that is ready for installation right out of the box, eliminating the need for an expensive trip to the dealership for programming.
Expert Pro Tip: Pre-Installation Check
Before you install your new PCM, take a moment to inspect the battery and the battery tray. On many of these GM trucks, the PCM is located directly beneath the battery. I’ve seen dozens of PCM failures caused by slow, unnoticed battery acid leaks that drip down and corrode the module’s casing and connectors. Clean the area thoroughly and ensure your battery is not leaking to protect your new investment.
Common Symptoms of a Failing 2003-2007 Sierra 3500 PCM
- โ Persistent Check Engine Light (CEL) with various communication or sensor codes.
- โ Harsh or delayed transmission shifting.
- โ Engine stalling, stumbling, or misfiring.
- โ Intermittent no-start or hard-starting conditions.
- โ Noticeable decrease in fuel mileage.
- โ Failure to pass an emissions test.
Plug-and-Play Installation: Get Your Truck Back on the Road
You don’t need to be a master technician to install this module. With basic hand tools, you can have your truck running smoothly again in under an hour.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: On most compatible models, it’s found on the driver’s side of the engine bay, under the battery or near the airbox.
- Disconnect Connectors: Carefully unclip the wiring harness connectors from the old PCM. Inspect them for any corrosion or damage.
- Remove Old Module: Unbolt the old PCM from its mounting bracket.
- Install New Module: Mount your new, pre-programmed PCM and securely reconnect the wiring harnesses.
- Reconnect Battery: Reattach the negative battery terminal. Your vehicle is now ready to start. In some cases, a security relearn procedure may be necessary, which can be done without special tools.
Guaranteed Compatibility
This PCM, part number 12602802, is a direct replacement for a wide range of GM trucks and SUVs from 2003 to 2007. It is also a compatible replacement for the following service numbers: 89017750, 12582605, 12589463, 89017734, and 28042802. Simply provide your VIN at checkout, and we’ll handle the rest, ensuring a perfect match for your vehicle’s specific configuration.