Restore Your Workhorse: The Reliable Fix for Your Van’s Brain
Is your 2005-2007 Chevrolet Express 1500 van running rough, stalling unexpectedly, or showing a persistent check engine light? As the central command center for your engine and transmission, a failing Powertrain Control Module (PCM) can cause a host of frustrating and hard-to-diagnose issues. Don’t let a faulty computer keep your work van off the road. This replacement PCM is the dependable, straightforward solution you need to restore your vehicle’s performance and reliability.
We take the guesswork and extra cost out of the repair. Unlike a generic module from a parts store, this unit arrives at your door pre-programmed with the latest official GM software updates, specifically matched to your van’s Vehicle Identification Number (VIN). This means no expensive trip to the dealership for programming—it’s ready for installation right out of the box. This is the most efficient way to get your van back in service.
Case Study: A Tricky Diagnosis
I remember a 2006 Express 1500 that came into my shop a few years back. The owner, a local plumber, was at his wit’s end. The van had an intermittent no-start condition and would occasionally shift harshly between first and second gear. He’d already replaced the crankshaft position sensor and a transmission solenoid at another shop, but the problem persisted. No specific sensor codes were present, just a generic P0606 (PCM Processor Fault) that would pop up now and then. After verifying power and ground to the module, I knew the issue was internal to the PCM itself. These units can develop micro-fractures on the circuit board from years of heat cycles and vibration, causing exactly these kinds of maddening, intermittent failures. A new, correctly programmed PCM fixed all his issues in one shot, and he was back on the job the next day.
Is Your Express Van Showing These Signs?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, your engine computer is a likely culprit:
- ✔ Check Engine Light is on with codes like P0601, P0602, P0606, or U0100.
- ✔ The engine cranks but refuses to start.
- ✔ Poor or erratic automatic transmission shifting.
- ✔ A significant drop in fuel economy for no apparent reason.
- ✔ Rough idling, stalling, or hesitation during acceleration.
- ✔ Communication errors with your diagnostic scan tool.
A Straightforward Guide to Installation
Replacing the PCM on your Express Van is a manageable job for a DIYer. No complex procedures are required, but a security/CASE relearn may be necessary after installation using a capable scan tool.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most 2005-2007 Express and Savana vans, the PCM is located in the engine compartment on the driver’s side, often near the firewall or master cylinder.
- Disconnect the Old Module: Carefully unplug the electrical connectors. These usually have a locking tab or lever that needs to be released.
- Swap the Modules: Unbolt the old PCM from its mounting bracket and secure the new module in its place.
- Reconnect Everything: Plug the wiring harnesses firmly into the new PCM until they click into place. Reconnect the negative battery terminal.
- Perform Relearn Procedure: Start the vehicle. In many cases, a Crankshaft Variation (CASE) relearn and security relearn will be required. This can be done with many professional-grade scan tools and ensures optimal communication between the new PCM and your vehicle’s systems.
Will This Fit My Vehicle?
This module is a direct replacement for part numbers 12589462, 12602801, and 89017749. It is guaranteed to fit the following vehicles, provided the options match:
- Chevrolet Express 1500 Van: 2005, 2006, 2007
- Chevrolet Express 2500/3500 Van: 2005, 2006, 2007
- GMC Savana 1500 Van: 2005, 2006, 2007
- GMC Savana 2500/3500 Van: 2005, 2006, 2007
- Chevrolet Silverado 1500/2500/3500 Pickup: 2005, 2006, 2007 (Classic)
- GMC Sierra 1500/2500/3500 Pickup: 2005, 2006, 2007 (Classic)
- Chevrolet Avalanche 2500: 2005, 2006
- Chevrolet Suburban 2500: 2005, 2006
- GMC Yukon XL 2500: 2005, 2006
- Chevrolet Blazer S10 / GMC Jimmy S15: 2005
- GMC Safari / Chevrolet Astro Van: 2005
- Cadillac CTS (V-Series): 2004, 2005 (ID 12589462 or 12602801)
Frequently Asked Questions
How do I provide my VIN?
After you complete your purchase, simply reply to your order confirmation email with your 17-digit VIN, or send it to us through our website’s contact form with your order number. We cannot program and ship the module without it.
Is this a plug-and-play part?
Yes, for the most part. It comes programmed to your VIN so the engine will start and run. However, for perfect operation and to prevent certain trouble codes, a security relearn and a Crankshaft Variation (CASE) relearn is often required using a compatible scan tool.
Why do you need my VIN?
Your VIN allows us to load the exact, correct software calibration for your vehicle’s specific engine, transmission, and emissions equipment. This ensures proper function and compatibility, just like a new module from the dealer.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the PCM (like codes P0601-P0606), then yes, this will resolve the issue. However, if the code is for a faulty sensor or other component, you will still need to repair that underlying problem.
What if my original part number is not 12602801?
This module is a direct replacement for several part numbers. As long as your original module’s part number is 12602801, 12589462, or 89017749, this unit will work perfectly for your application.