Restore Your Truck’s Power and Reliability
As a technician with over two decades of experience under the hood, I understand the frustration when your truck’s brain—the Powertrain Control Module (PCM)—starts to fail. You’re dealing with a check engine light that won’t quit, unpredictable stalling, poor fuel mileage, or even a truck that refuses to start. This isn’t just an inconvenience; it’s a hit to your productivity and peace of mind. This replacement PCM, part number 89017739, is the definitive solution for your 2004 Sierra 2500 PCM issues and a wide range of other GM vehicles from that era.
What sets this module apart is our professional programming service. Before we ship it, we flash the unit with the latest official GM software updates, tailored specifically to your truck using the Vehicle Identification Number (VIN) you provide. This means you get a component that’s not just a replacement, but a fully updated part ready for immediate installation. You bypass the expensive trip to the dealership for programming, saving you both time and hundreds of dollars in labor costs. It’s the same reliable fix I’d perform in my own shop, delivered directly to you.
Case Study: A Tricky Diagnosis
I once had a 2004 Silverado 2500 with the 8.1L in the bay that was a real head-scratcher. The owner complained of random stalling at traffic lights and occasional hard starting, but with no consistent check engine codes. We checked fuel pressure, sensors, and wiring—everything seemed fine. On a hunch, I monitored the PCM data stream during a long test drive and finally caught it: the processor would momentarily drop communication. It was a classic sign of internal PCM failure due to heat cycles and vibration. We installed a VIN-programmed module just like this one, and the truck has run flawlessly for the owner ever since. These intermittent issues are often the first sign, and this 2004 Sierra 2500 PCM is the precise fix.
Is Your Truck Showing These Telltale Signs?
- ✔ Persistent Check Engine Light (CEL)
- ✔ Engine stalling or cutting out unexpectedly
- ✔ Rough or erratic idling
- ✔ A noticeable drop in fuel economy
- ✔ Harsh or incorrect transmission shifting
- ✔ The engine cranks but refuses to start
- ✔ Diagnostic Trouble Codes (DTCs) stored, such as P0601, P0602, or P0606, indicating internal module failure.
A Straightforward Guide to Installation
Installing your new PCM is a job most DIYers can handle with basic hand tools. The key is taking your time and following the proper procedure. For your 2004 Sierra 2500, the PCM is located on the driver’s side, under the battery tray.
- Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts.
- Access the Module: You will likely need to remove the battery and the battery tray to gain clear access to the PCM. Keep track of any bolts you remove.
- Disconnect the Connectors: The PCM has several large electrical connectors. Each has a locking tab or lever. Carefully release the locks and gently pull the connectors straight out from the module. Never force them.
- Remove the Old PCM: Unbolt the old module from its mounting bracket. Note its orientation before removing it.
- Install the New PCM: Mount your new, pre-programmed PCM onto the bracket. Ensure it’s secure.
- Reconnect Everything: Plug the electrical connectors back into the new module until they click and lock into place. Reinstall the battery tray and the battery, then reconnect the negative battery terminal.
- Security Relearn Procedure: In many cases, you will need to perform a simple security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. This allows the new PCM to synchronize with your vehicle’s anti-theft system. Consult your owner’s manual for the specific procedure for your truck.
Verified Vehicle Compatibility
This module is a direct replacement for part numbers 89017739 and 12586243. It fits a broad range of 2004 GM models, but always verify your specific application. Key fitments include:
- ✔ 2004 Chevrolet Avalanche 2500
- ✔ 2004 Chevrolet Corvette (ID 12586243)
- ✔ 2004-2005 Cadillac CTS (V-Series, ID 12586243)
- ✔ 2004 Chevrolet Express / GMC Savana Vans (1500, 2500, 3500)
- ✔ 2004 Chevrolet S10 / GMC Sonoma / Chevrolet Blazer / GMC Jimmy
- ✔ 2004 GMC Sierra & Chevrolet Silverado 1500 (4.3L)
- ✔ 2004 GMC Sierra & Chevrolet Silverado 2500 / 3500 (Gasoline, 8.1L)
- ✔ 2004 GMC Yukon XL 2500 / Chevrolet Suburban 2500 (8.1L)
- ✔ 2004 GMC Envoy / Chevrolet Trailblazer / Buick Rainier (5.3L, check ID)
- …and many other models listed in the compatibility chart.
What exactly is VIN programming?
What exactly is VIN programming?
VIN programming is the process of loading your vehicle’s unique 17-digit Vehicle Identification Number (VIN) and its specific operational software onto the PCM. This ensures the module communicates correctly with your engine, transmission, and other systems for optimal performance and fuel efficiency, just as it would from the factory. We handle this for you before shipping.
Do I need to do anything after installing this PCM?
Because this module comes pre-programmed, the primary step after physical installation is often a security relearn procedure. This is a simple key-cycle process that you can do yourself in about 30 minutes and requires no special tools. This syncs the new PCM with your truck’s anti-theft system.
How do I find my original part number?
The part number is printed on a sticker on the case of your current PCM. You will need to locate the module on your vehicle to read it. This unit is a direct replacement for part numbers 89017739 and 12586243.
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, a check engine light can be triggered by many other things, like a bad sensor or a loose gas cap. It’s always best to have the codes read with a scanner to properly diagnose the issue before ordering.