Is Your Workhorse Van Suddenly Unreliable?
As a technician with over 20 years of experience under the hood, I know the frustration when a dependable vehicle like your 2003 Chevy Express Van starts acting up. Intermittent stalling, a persistent check engine light, or a complete no-start condition can bring your work or travels to a grinding halt. Often, the culprit is a failing Powertrain Control Module (PCM)—the electronic brain of your vehicle. When it malfunctions, it can cause a cascade of confusing and costly problems. This isn’t just an inconvenience; it’s a critical failure that needs a reliable solution.
This isn’t just a replacement part; it’s a complete, ready-to-install fix. We take a high-quality replacement PCM, part number 89017733, and flash it with the latest official GM software updates specifically for your vehicle. By providing us with your Vehicle Identification Number (VIN) at checkout, you receive a module that is 100% matched to your van’s original specifications. This process restores factory performance, fuel efficiency, and emissions control, eliminating the need for an expensive trip to the dealership for programming.
Is Your Van Exhibiting These Telltale Signs?
A failing PCM can manifest in various ways. Over the years in my shop, I’ve diagnosed hundreds of these specific modules. If you’re experiencing any of the following, a faulty engine computer is a likely cause:
- ✔ Check Engine Light is on with communication error codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault).
- ✔ The engine cranks but refuses to start.
- ✔ Rough idling, stalling, or hesitation during acceleration.
- ✔ Noticeable decrease in fuel economy.
- ✔ Transmission shifting erratically or harshly.
- ✔ Failure to pass an emissions or smog test.
Case Study: The Ghost in the Machine
I remember a 2003 Savana 2500 that came into my bay with a truly baffling issue. The owner had already replaced the fuel pump and crank sensor, but the van would still randomly die at stoplights. No consistent codes, just pure frustration. After confirming power and ground to the PCM were solid, I suspected an internal module failure. Instead of a costly new unit from the dealer, we ordered a pre-programmed module like this one. After a 15-minute install and a quick security relearn, the van ran perfectly. The problem was gone for good. It saved the customer hundreds in diagnostic time and parts.
Your Straightforward Installation Guide
Getting your van back on the road is simpler than you think. This pre-programmed 2003 Express 2500 PCM is designed for a direct-fit replacement. While professional installation is always an option, a confident DIYer can handle this job with basic hand tools.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On the 2003 Express and Savana vans, the PCM is typically located in the engine compartment on the driver’s side, towards the rear.
- Disconnect the Old Module: Carefully unplug the electrical connectors. These usually have a locking tab or lever that needs to be released. Avoid pulling on the wires themselves.
- Remove the Old PCM: Unbolt the module from its mounting bracket. Keep the hardware as you will reuse it.
- Install the New PCM: Mount your new, pre-programmed module onto the bracket and securely plug in the electrical connectors. You should feel a solid click as they lock into place.
- Reconnect the Battery: Reattach the negative battery terminal.
- Perform Security Relearn (If Needed): In many cases, you may need to perform a simple key-cycle security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating 2-3 times. This allows the vehicle’s anti-theft system to recognize the new PCM.
Verified Compatibility for Your GM Vehicle
This module is a direct replacement for service number 89017733 and other cross-compatible numbers. Please verify your vehicle is on this list to ensure a perfect fit:
- ✔ 2003-2004 Cadillac CTS (Base, ID 12581565)
- ✔ 2004 Chevrolet Corvette (ID 12581565)
- ✔ 2003 Chevrolet Astro / GMC Safari
- ✔ 2003 Chevrolet Blazer S10 / GMC Jimmy S15
- ✔ 2003 Chevrolet S10 / GMC Sonoma (4.3L)
- ✔ 2003 Chevrolet Avalanche 2500
- ✔ 2003 Chevrolet Express / GMC Savana 1500, 2500, 3500 Vans
- ✔ 2003 Chevrolet Silverado / GMC Sierra 1500 (4.3L)
- ✔ 2003 Chevrolet Silverado / GMC Sierra 2500 & 3500 (8.1L Gas)
- ✔ 2003 Chevrolet Suburban 2500 / GMC Yukon XL 2500 (8.1L)
Frequently Asked Questions
What does ‘programmed to my VIN’ mean?
It means we load the module with the specific software and calibrations from GM that match your vehicle’s exact build, including engine, transmission, and emissions equipment. This makes the installation process much simpler and ensures correct vehicle operation.
How do I provide you with my VIN?
After you complete your purchase, you will receive instructions on how to send us your 17-digit Vehicle Identification Number (VIN). We cannot ship the part until we receive this information.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the PCM (like code P0601), then yes, this part is the correct fix. However, it will not fix issues caused by other faulty sensors or components on the vehicle. Proper diagnosis is key.
Is a security relearn procedure difficult?
Not at all. For most GM vehicles of this era, it’s a simple key-cycle procedure that takes about 30 minutes and requires no special tools. We can provide general instructions upon request.
Where is the PCM located on my 2003 Express 2500 Van?
You’ll find the Powertrain Control Module in the engine compartment, mounted on the driver’s side (LH) towards the rear firewall.