Restore Your Truck’s Brainpower and Performance

Is your GMC Sierra 3500 throwing confusing check engine lights, running rough, or refusing to start? As a mechanic with over two decades of experience under the hood, I’ve seen these exact symptoms countless times. Often, the culprit isn’t a dozen different sensors, but the single component that controls them all: the Powertrain Control Module (PCM). This isn’t just a replacement part; it’s a direct solution to restore your truck’s reliability and drivability, getting you back to work without the dealership hassle.

This module, part number 89017749, is the central command for your engine and transmission. When it fails, it can cause a cascade of frustrating, intermittent problems that are tough to pin down. We solve this by providing a high-quality replacement PCM that is professionally programmed to your truck’s specific Vehicle Identification Number (VIN). We install the latest GM software updates, ensuring optimal fuel economy, emissions compliance, and engine performance right out of the box. This is the definitive fix for a faulty 2005-2007 Sierra 3500 PCM.

Is Your Truck Showing These Symptoms?

A failing PCM can manifest in many ways. If you’re experiencing any of the following, it’s a strong indicator that your module needs attention. Look out for these common signs and associated Diagnostic Trouble Codes (DTCs):

• ✔ Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (PCM Processor Fault).
• ✔ The engine cranks but refuses to start.
• ✔ Unexplained drops in fuel economy.
• ✔ Harsh or erratic automatic transmission shifting.
• ✔ Stalling, stumbling, or rough idling for no apparent reason.
• ✔ Loss of communication with your scan tool.

A Straightforward Guide to Installation

Replacing your 2005-2007 Sierra 3500 PCM is a job most DIYers can handle in their own driveway. Since we program the module before shipping, you won’t need any special scan tools for programming. Just follow these steps carefully.

1. Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait 10-15 minutes to allow the system to fully discharge.
2. Locate the PCM: On most Sierra/Silverado trucks, the PCM is located under the hood on the driver’s side, near or under the battery tray.
3. Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors from the old PCM. These connectors have locking tabs; be gentle to avoid breaking them.
4. Remove the Old Module: Unbolt the PCM from its mounting bracket. Keep the hardware, as you may need it for the new module.
5. Install the New PCM: Mount your new, pre-programmed PCM onto the bracket and securely fasten it.
6. Reconnect Everything: Plug the wiring harnesses back into the new module until they click firmly into place. Reconnect the negative battery terminal.
7. Perform Security Relearn (If Necessary): In most cases, you will need to perform a simple security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. This allows the new PCM to sync with your vehicle’s anti-theft system. Consult your owner’s manual for the exact procedure for your vehicle.

Will This Fit My Vehicle?

We guarantee compatibility for this 2005-2007 Sierra 3500 PCM. This module is a direct replacement for part numbers 89017749, 12589462, and 12602801 and fits a wide range of GM vehicles. Please verify your model and options below: