Restore Peak Performance to Your Workhorse Van
Is your 2003 Chevy Express 3500 Van acting up? Unexplained stalling, rough idling, a persistent Check Engine Light, or even a frustrating no-start condition can bring your work to a halt. As a technician with over two decades of experience, I’ve seen these exact issues countless times, and they often trace back to one critical component: a failing Powertrain Control Module (PCM). This isn’t just a part; it’s the central computer of your vehicle, responsible for managing everything from fuel injection and ignition timing to transmission shifting. When it falters, your van’s reliability disappears.
This replacement PCM, part number 89017733, is the definitive solution to get your van running correctly again. We take the guesswork and hassle out of the repair by pre-programming the module specifically for your vehicle. Simply provide us with your Vehicle Identification Number (VIN) after your purchase, and we’ll flash the unit with the latest, most stable software updates directly from GM. This ensures seamless communication with your van’s other systems and restores its original factory performance and efficiency.
A Technician’s Notebook: The Intermittent Stall
A local contractor brought in his ’03 Express 3500. The complaint was maddening: it would run perfectly for days, then suddenly stall at a stoplight and refuse to restart for 10-15 minutes. No consistent codes were stored, just a history of random communication faults. After checking all the usual suspects—fuel pressure, crank sensor, wiring harnesses—we focused on the PCM. On the bench, we found that heat soak was causing an internal circuit board failure. After it cooled, it worked again. Replacing the PCM with a properly programmed unit like this one solved the problem permanently. It’s a classic failure mode for these hard-working vehicles.
Common Signs of a Failing PCM
- ✔ Unexplained stalling or engine hesitation
- ✔ Difficulty starting the engine or a complete no-start condition
- ✔ Harsh or erratic automatic transmission shifting
- ✔ A persistent Check Engine Light with codes like P0601, P0605, or P0606 (Internal Control Module Memory Check Sum Error)
- ✔ Decreased fuel economy
- ✔ Misfire codes that don’t resolve with new plugs or coils
Your Guide to a Simple PCM Installation
Replacing the 2003 Express 3500 PCM is a straightforward job you can do with basic hand tools. Follow these steps carefully for a successful installation.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental reconnection.
- Locate the Module: On the Express and Savana vans, the PCM is typically found in the left-hand (driver’s side) rear of the engine compartment.
- Disconnect the Connectors: Carefully release the locking tabs on the wiring harness connectors and pull them straight out from the module. Avoid pulling on the wires themselves. Inspect the connectors for any corrosion or damage.
- Remove the Old PCM: Unbolt the mounting hardware that secures the old PCM to its bracket. Remove the faulty module from the vehicle.
- Install the New PCM: Mount your new, pre-programmed PCM onto the bracket and secure it with the original hardware.
- Reconnect and Secure: Firmly plug the wiring harness connectors into the new module until they click into place. Reconnect the negative battery terminal.
- 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. Your van is now ready to start.
Will This Fit My Vehicle?
This module is a direct replacement for service number 89017733 and many others. It is guaranteed to be compatible with the following 2003 and 2004 GM models. Please verify your vehicle is on this list before ordering.
AVALANCHE 2500, ASTRO, BLAZER S10/JIMMY S15, EXPRESS 1500/2500/3500 VAN, S10/S15/SONOMA (4.3L), SAFARI, SAVANA 1500/2500/3500 VAN, SIERRA 1500 PICKUP (4.3L), SIERRA 2500/3500 PICKUP (Gasoline, 8.1L), SILVERADO 2500/3500 PICKUP (Gasoline, 8.1L), SUBURBAN 2500 (8.1L), YUKON XL 2500 (8.1L)
2004 Models:
CTS (Base, ID 12581565), CORVETTE (ID 12581565)
Frequently Asked Questions
Do I need to do anything after installing this PCM?
Because we pre-program the module to your VIN, it is a direct plug-and-play installation. In some cases, a simple 10-15 minute key-on security relearn procedure may be required. No dealer visit is necessary.
What information do you need from me?
After you place your order, you must provide us with your 17-digit Vehicle Identification Number (VIN). This is critical for us to load the correct GM-certified software for your specific vehicle configuration.
What is the difference between a PCM, ECM, and ECU?
These terms are often used interchangeably. PCM (Powertrain Control Module) is the most accurate for this part as it controls both the engine (Engine Control Module – ECM) and the transmission. ECU (Electronic Control Unit) is a more generic term.
Will this fix my transmission shifting problems?
If your shifting problems are caused by faulty electronic commands from the PCM, then yes, this part will resolve them. The PCM controls transmission line pressure and shift points, so a failing unit can cause harsh or erratic shifting.
Is this a new or used part?
This is a high-quality, inspected, and tested replacement part, guaranteed to function to OEM specifications. We program it with the newest software available from GM for your vehicle.