Is Your Tahoe or GM Truck Running Rough?
If you’re dealing with a persistent check engine light, poor fuel mileage, erratic shifting, or even a frustrating no-start condition, the problem often points directly to the brain of your engine: the Powertrain Control Module (PCM). Over my 20+ years turning wrenches, I’ve seen countless GM trucks and SUVs sidelined by a failing PCM. It’s a common issue, but the solution doesn’t have to be a complicated or expensive trip to the dealership.
This is a direct-fit replacement PCM, service number 89017750, for a wide range of 2003-2007 GM vehicles. The best part? We handle the programming for you. Simply provide your vehicle’s VIN during checkout, and we’ll flash the module with the latest, most stable software updates from GM. It arrives at your door ready to install, saving you hundreds in dealer programming fees.
The Right Fix for Common Powertrain Problems
A faulty 2003-2006 Tahoe PCM can cause a host of issues that are often misdiagnosed. Before you start replacing expensive sensors or fuel system components, consider if your vehicle is showing these classic signs of PCM failure:
- โ Unexplained Check Engine Light (CEL) with codes like P0601, P0602, or P0606
- โ Engine stalling, sputtering, or misfiring
- โ Harsh or incorrect automatic transmission shifting
- โ Poor acceleration and reduced power
- โ Decreased fuel economy
- โ Complete no-start or intermittent starting problems
Real-World Diagnosis: A Story from the Shop
“A customer’s ’05 Tahoe came in last week with a P0601 code (Internal Control Module Memory Check Sum Error) that just wouldn’t clear. They had already replaced two coil packs and the crank sensor with no luck. The symptoms were intermittent stalling and a hard 1-2 shift. We verified power and ground to the PCM connectors, which were perfect. The issue wasn’t the wiring or sensors, but the processor on the board itselfโa common failure point I’ve seen on hundreds of these P59 controllers. We installed one of our pre-programmed PCMs, performed the security relearn, and it fired right up, shifting smoothly. It’s a 30-minute fix that solves a major headache.”
Plug-and-Play Installation: No Dealer Visit Required
Replacing your 2003-2006 Tahoe PCM is a straightforward job you can do in your own driveway. On most of these trucks and SUVs, the module is located in the engine bay on the driver’s side, right under the battery tray.
- Safety First: Disconnect the negative battery terminal and secure it away from the post.
- Locate the PCM: Find the module, which has three large multi-pin connectors. On most models like the Tahoe, Silverado, and Suburban, you may need to remove the battery to access it.
- Disconnect the Connectors: Carefully lift the gray levers on each of the three connectors to release them from the module. Never force them. Inspect the pins for any corrosion or damage.
- Remove the Old Module: Unbolt the PCM from its mounting bracket.
- Install the New Module: Bolt your new, pre-programmed PCM into place. Reconnect the three wiring harnesses, ensuring the levers click securely into the locked position.
- Reconnect Battery: Reinstall the battery (if removed) and reconnect the negative terminal.
- Perform Security Relearn: You will need to perform a simple security relearn procedure (often called a CASE relearn or Passlock relearn) so the vehicle recognizes the new PCM. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Your vehicle’s manual will have the exact steps.
Guaranteed Compatibility
This module is a direct replacement for service numbers 89017750, 12582605, 12589463, 12602802, 89017734, and 28042802. It fits a huge range of GM trucks and SUVs, including the Silverado, Sierra, Suburban, Yukon, Escalade, Hummer H2, and more. Please check the detailed fitment list to confirm it’s the right part for your specific year and model. By providing your VIN, you guarantee we send a perfectly matched and correctly programmed computer for your vehicle’s exact configuration.