Restore Peak Performance to Your 2003 Avalanche 2500
Is your 2003 Chevrolet Avalanche 2500 running rough, throwing confusing check engine light codes, or failing to start altogether? These are classic signs of a failing Powertrain Control Module (PCM), the central computer that manages your truck’s engine and transmission. A faulty PCM can lead to a cascade of issues, including poor fuel economy, erratic shifting, and even complete engine shutdown. This replacement PCM, part number 89017733, is the definitive solution to restore your vehicle’s reliability and drivability.
This isn’t just a generic, off-the-shelf part. We provide a fully programmed module tailored specifically to your vehicle. When you place your order, you’ll provide us with your truck’s Vehicle Identification Number (VIN). Our technicians then use that VIN to flash the module with the latest, most stable software updates directly from General Motors. This critical step ensures that the PCM communicates perfectly with your engine, transmission, and all other onboard systems, just as it did the day it left the factory. This eliminates the need for an expensive trip to the dealership for programming, saving you both time and money.
From the Diagnostic Bay
We had a 2003 Silverado 2500 with the 8.1L V8 (which uses this exact same PCM) come into the shop with a persistent P0300 random misfire code. The owner had already spent a fortune replacing spark plugs, wires, ignition coils, and even the fuel pump. Nothing worked. The truck still idled poorly and lacked power. After hooking up our professional scan tool, we noticed the fuel trim and ignition timing data were completely erratic. We suspected the PCM. After installing one of our pre-programmed modules, the truck fired up and idled perfectly. All data parameters returned to normal. The customer had been chasing a ghost created by a faulty computer—a common and frustrating scenario that a new, correctly programmed module solves instantly.
Key Features of This 2003 Avalanche 2500 PCM
- ✔ VIN-Programmed for Your Truck: Arrives flashed with the latest GM software specific to your vehicle. No dealer visit required for programming.
- ✔ Direct-Fit Replacement: Engineered to be a precise replacement for OEM part number 89017733 and other compatible service numbers.
- ✔ Restores Original Functionality: Corrects common issues like check engine lights, poor shifting, rough idle, and no-start conditions.
- ✔ Broad Compatibility: Fits a wide range of 2003-2004 GM trucks, vans, and SUVs, including the Sierra, Silverado, Suburban, Yukon XL, Express, and Savana. Please verify your part number and application.
- ✔ Quality Tested: Each unit is inspected to ensure it meets strict performance and reliability standards.
Common Symptoms of a Failing PCM
If you’re experiencing any of the following issues, a failing PCM could be the root cause. This module is designed to correct these problems and get your vehicle running smoothly again.
- ✔ Check Engine Light is on with various, often inconsistent, trouble codes.
- ✔ Engine cranks but refuses to start.
- ✔ Rough or unstable idling.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Engine stalling or misfiring for no apparent reason.
- ✔ Communication errors with diagnostic scan tools.
Installation and Post-Installation Steps
On the 2003 Avalanche 2500, the PCM is typically located on the driver’s side, under the battery tray. Installation involves disconnecting the vehicle’s battery, removing the old module, and connecting the new one. While the module is programmed for your engine and transmission, you will need to perform a security relearn procedure (often called an anti-theft relearn or Passlock relearn) after installation. This simple procedure syncs the new PCM with your vehicle’s anti-theft system and can usually be done in your driveway with just the ignition key. Instructions for this procedure are widely available online or in your vehicle’s service manual.
Frequently Asked Questions
Why do you need my VIN to program the PCM?
Your Vehicle Identification Number (VIN) contains specific information about your truck’s engine, transmission, emissions systems, and other options. We use the VIN to load the exact GM-certified software for your vehicle’s configuration, ensuring perfect communication and operation of all systems.
Is this a plug-and-play part?
Almost. It is pre-programmed to your VIN, which handles the most complex part of the process. However, after installation, you must perform a security relearn procedure. This syncs the new module to your vehicle’s anti-theft system and is required for the engine to start and run.
Will this fix my check engine light?
If the check engine light and associated codes are being caused by a faulty PCM, then yes, this part will resolve the issue. It’s crucial to ensure that the problem isn’t with a sensor or another component before replacing the PCM.
Where is the PCM located on my 2003 Avalanche 2500?
On the 2003 Avalanche 2500, the Powertrain Control Module is located in the engine bay on the driver’s side, typically mounted to a bracket underneath the battery and battery tray.
What if I install it and my truck doesn’t start?
The most common reason for a no-start condition after installation is an incomplete or failed security relearn procedure. Please ensure you have correctly followed the steps for the anti-theft relearn. If issues persist, double-check all electrical connections and ensure the battery is fully charged.