Is Your 2003 GM Truck or Van Running Rough?
If you’re dealing with a persistent check engine light, erratic engine behavior, harsh shifting, or even a no-start condition, a failing Powertrain Control Module (PCM) is often the culprit. In my 20+ years as a diagnostician, I’ve seen countless GM vehicles from this era sidelined by a faulty computer. The PCM is the brain of your vehicle, controlling everything from fuel injection and ignition timing to transmission shift points. When it fails, the symptoms can be confusing and frustrating, often mimicking other part failures.
The Smart Solution: A VIN-Programmed PCM
Forget expensive dealership visits and the hassle of finding a local shop with the right programming equipment. This module is the direct, effective solution you need. We take the guesswork out of the repair by pre-programming this PCM specifically for your vehicle using your VIN. This ensures 100% compatibility and installs the latest, most stable software updates from General Motors, often correcting factory bugs you didn’t even know you had.
- โ VIN Programmed & Ready to Install: Provide your Vehicle Identification Number at checkout, and we’ll flash the module before it ships.
- โ No Dealer Visit Required: This is a true plug-and-play solution, saving you hundreds in programming fees and towing costs.
- โ Solves Common Issues: Effectively resolves problems like false sensor codes, poor fuel economy, transmission issues, and intermittent stalling.
- โ Latest GM Software: We load the most current calibrations to improve performance and reliability over the original software.
Expert Pro Tip: Check Your Grounds Before Installation
Before you even unbolt the old PCM, do this one critical check: inspect the main ground straps. On these GM trucks, there’s a primary ground from the engine block to the frame and another from the battery to the body/frame. Over time, they get corroded and brittle. A poor ground can cause voltage spikes that will instantly damage a new module. I’ve seen it happen. Take 10 minutes to clean the contact points with a wire brushโit’s the best insurance for your new part.
Simple, Straightforward Installation
Replacing the PCM on most of these GM vehicles is a job most DIY mechanics can handle in under an hour. While locations vary slightly, the process is generally the same.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: On a 2003 Sierra 1500, it’s typically found on the driver’s side of the engine bay, under the battery tray. On Express/Savana vans, it’s on the driver’s side rear of the engine compartment.
- Disconnect Connectors: Carefully unclip the wiring harness connectors. They have locking tabs that need to be released. Avoid pulling on the wires themselves.
- Remove the Old Module: Unbolt the PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Seat your new, pre-programmed PCM into the bracket and secure it. Reconnect the wiring harnesses until they click securely in place.
- Reconnect Battery: Re-attach the negative battery terminal. The vehicle may need to complete a security relearn procedure, which typically involves turning the key to the ‘ON’ position for 10-15 minutes. Your vehicle’s service manual will have the exact steps if required.
Guaranteed Compatibility for Your Vehicle
This module, part number 89017733, is a direct replacement for a wide range of GM vehicles. It replaces numerous original service numbers, ensuring a perfect match. Please confirm your vehicle is on the list below. If you’re unsure, just send us your VIN, and we’ll verify compatibility for you.
Replaces Part Numbers: 12581565, IS 8125815650, 12570557, 12570558, 12576106, 12576869, 12578127, 8125781270, 88864822, 89017733
Fitment Includes:
- 2003-2004 Cadillac CTS (Base)
- 2004 Chevrolet Corvette
- 2003 Chevrolet Avalanche 2500
- 2003 Chevrolet Blazer S10 / GMC Jimmy S15
- 2003 Chevrolet S10 / GMC Sonoma (4.3L)
- 2003 Chevrolet Astro / GMC Safari
- 2003 Chevrolet Express & GMC Savana Vans (1500, 2500, 3500)
- 2003 Chevrolet Silverado & GMC Sierra 1500 (4.3L)
- 2003 Chevrolet Silverado & GMC Sierra 2500/3500 (Gasoline, 8.1L)
- 2003 Chevrolet Suburban 2500 / GMC Yukon XL 2500 (8.1L)
Don’t let a bad computer keep your truck off the road. This pre-programmed 2003 Sierra 1500 PCM is the most reliable and cost-effective way to restore your vehicle’s function and get back to driving with confidence.