1998-1999 GMC 3500 PCM 09366810 | Programmed to Your VIN for Easy Install

Restore Your Truck’s Heartbeat and Performance

Is your dependable GMC 3500 suddenly giving you trouble? Erratic shifting, a persistent Check Engine Light, or a frustrating no-start condition can sideline your workhorse and disrupt your life. These are classic signs of a failing Powertrain Control Module (PCM), the electronic brain of your vehicle. This replacement PCM is the definitive solution, engineered to restore the smooth operation and steadfast reliability you depend on. We take the guesswork out of the repair by pre-programming the module to your truck’s specific VIN, ensuring it’s ready for a straightforward installation right out of the box. Get back the confidence of a truck that runs like it should.

Warning Signs Your PCM Needs Attention

A failing engine computer can manifest in numerous ways. If you’re experiencing any of the following, this module is the likely solution to get you back on the road with confidence.

• ✔ Check Engine Light: The module may trigger various Diagnostic Trouble Codes (DTCs), most notably P0601 (Internal Control Module Memory Check Sum Error) or P0605 (Internal Control Module ROM Error).
• ✔ Erratic Shifting: Harsh or delayed gear changes, or getting stuck in a single gear, often point to a communication breakdown originating in the PCM.
• ✔ Poor Engine Performance: Noticeable loss of power, rough idling, stalling, and decreased fuel economy are common symptoms.
• ✔ No-Start Condition: The engine may crank but refuse to start if the PCM isn’t properly managing fuel delivery and spark.
• ✔ Communication Errors: Your diagnostic scan tool may be unable to communicate with the PCM, indicating a total failure.

Guided Installation for Your 1998-1999 GMC 3500 PCM

Replacing the PCM is a manageable job for a DIYer with basic tools. Our pre-programming service makes it a plug-and-play process. Follow these steps for a successful installation.

1. Safety First: Begin by disconnecting the negative terminal of your vehicle’s battery to prevent any electrical shorts.
2. Locate the Module: On most 1998-1999 GMC trucks, the PCM is located in the engine compartment, typically on the driver’s side near the firewall or inner fender.
3. Disconnect the Old Unit: Carefully unplug the electrical connectors from the old PCM. These connectors have locking tabs that need to be released before they can be pulled free.
4. Swap the Modules: Unbolt the old PCM from its mounting bracket and set it aside. Mount your new, pre-programmed module in its place and secure it with the original hardware.
5. Reconnect and Secure: Firmly plug the electrical connectors into the new PCM, ensuring they click into place. Reconnect the negative battery terminal.
6. Final Steps: In some cases, a security relearn procedure may be necessary. This can typically be done by turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times before starting the engine. Consult your vehicle’s service information for exact steps.

Expert Tip: Check Your Grounds

Before installing your new PCM, take a moment to inspect and clean the main engine and chassis ground connections. A poor ground can cause voltage issues that mimic PCM failure and can damage a new module. A few minutes with a wire brush can save you from future headaches and ensure a lasting repair.

Guaranteed Fit for Your Vehicle

This module is a direct replacement for part numbers 09366810, 16250279, and 09355699. It is engineered to fit the following makes and models:

Frequently Asked Questions