Restore Peak Performance to Your GM Truck or SUV
Is your truck or SUV suffering from a mind of its own? A faulty Powertrain Control Module (PCM), the vehicle’s central computer, can cause a cascade of frustrating issues, from a persistent Check Engine Light to a no-start condition that leaves you stranded. After more than two decades in the garage, I’ve seen firsthand how a failing PCM can mimic a dozen other problems. This isn’t just a part; it’s the solution to getting your reliable vehicle back.
This replacement PCM, part number 89017734, is the definitive fix for a wide range of popular GM vehicles. We take the guesswork and hassle out of the repair by programming the module specifically to your vehicle’s VIN before it ships. This means it arrives loaded with the latest GM software updates, ensuring optimal performance, fuel efficiency, and emissions control right out of the box. You get a direct-fit, plug-and-play solution without the expensive trip to the dealership for programming.
Case Study: A Tricky Diagnosis
A customer brought in a 2005 Silverado 2500 with the 6.0L engine. The complaint was intermittent stalling and a flashing Check Engine Light with code P0606 (PCM Processor Fault). We checked all the basics—power, grounds, and wiring harnesses—and everything was solid. The symptoms pointed directly to an internal failure of the PCM. Instead of a costly dealer part and programming fee, we installed one of our VIN-programmed modules. The swap took less than 30 minutes, the code cleared, and the truck ran perfectly. This is a classic scenario where this part provides a fast, reliable, and cost-effective repair.
Is Your GM Truck Showing These Signs?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, a faulty module is a likely culprit:
- ✔ Check Engine Light is on with communication-related Diagnostic Trouble Codes (DTCs) like P0601, P0602, P0606, or U0100.
- ✔ The engine cranks but refuses to start.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Engine stalling, stuttering, or running rough for no apparent reason.
- ✔ Other warning lights (like ABS or security) illuminate unexpectedly.
DIY-Friendly Installation: Get Your Truck Running Right
Replacing the PCM on these GM trucks is a straightforward job for a confident DIYer or any professional technician. Our pre-programming service eliminates the most complex step, saving you time and money.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 10 minutes to allow the system to fully discharge.
- Locate the PCM: On most compatible models, the PCM is located in the engine bay, either on the driver’s side next to the airbox or under the battery tray.
- Disconnect and Remove: Carefully unplug the electrical connectors. Most have a lever or tab that needs to be released. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed PCM into place. Reconnect the electrical connectors, ensuring they click securely into position.
- Reconnect Power: Reattach the negative battery terminal.
- Perform Security Relearn: In many cases, you’ll need to perform a simple key-cycle security relearn procedure. Turn the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds. Repeat this process 3 times. On the fourth cycle, the vehicle should start and run normally.
Verified Vehicle Compatibility List
This module is a direct replacement for service numbers 89017750, 12582605, 12589463, 12602802, 89017734, and 28042802. Please verify your part number and check the list below to ensure a perfect fit for your vehicle.
- Avalanche 1500 (2003-2006)
- Cadillac Escalade, ESV, EXT (2003-2006)
- Chevrolet SSR (2003)
- Chevrolet Silverado 1500, 2500, 3500 (2003-2007 Classic)
- Chevrolet Suburban 1500, 2500 (2003-2006)
- Chevrolet Tahoe (2003-2006)
- Chevrolet Trailblazer EXT (2003, 5.3L)
- GMC Envoy XL (2003, 5.3L)
- GMC Sierra 1500, 2500, 3500 (2003-2007 Classic)
- GMC Sierra Denali (2003-2007 Classic)
- GMC Yukon, Yukon XL 1500, Yukon XL 2500 (2003-2006)
- Hummer H2 (2003-2007)
- Isuzu Ascender (2003, 5.3L)
Frequently Asked Questions About This PCM
Frequently Asked Questions
What is VIN programming and why do I need it?
VIN programming involves loading your vehicle’s specific Vehicle Identification Number (VIN) and the latest GM-approved software onto the PCM. This ensures the computer communicates correctly with your engine, transmission, and security systems, making the installation plug-and-play and avoiding a trip to the dealer.
How do I provide my VIN?
After you complete your purchase, you will need to send us your 17-digit VIN. We cannot program and ship the module without it. Please double-check it for accuracy to prevent delays.
Do I need to do anything else after installing this 2003 Trailblazer EXT PCM?
In most cases, you will need to perform a simple security relearn procedure, which involves cycling the key. We include instructions for this common and easy-to-perform step. No special tools are required.
How can I be sure this part is compatible?
The best way is to match the service number on your current PCM to one of the numbers listed (e.g., 89017734, 12602802). You can also use the detailed vehicle compatibility list provided on this page to confirm fitment for your make, model, and year.