Restore Your Van’s Performance and Reliability
Is your 2005-2007 GMC Savana 3500 van running rough, stalling unexpectedly, or showing a persistent check engine light? These are classic signs that the brain of your engine, the Powertrain Control Module (PCM), is failing. As a technician with over two decades of experience under the hood, I’ve seen firsthand how a faulty PCM can cause a host of frustrating and hard-to-diagnose issues. This isn’t just a part; it’s the central command center for your vehicle’s engine and transmission performance. Replacing it with a generic, un-programmed unit from a big box store often leads to more problems and a trip to the dealership for expensive programming.
This replacement PCM, part number 12602801, is the definitive solution. We take the guesswork and hassle out of the repair by programming the module specifically for your vehicle using your VIN. This ensures it arrives with the latest GM factory software updates, restoring original performance, fuel efficiency, and emissions control. It’s a direct-fit solution designed to get your workhorse van back on the road, operating as it should.
Case Study: The Ghost in the Machine
A local contractor brought in his ’06 Savana 3500. The van would randomly stall at stoplights, but with no consistent check engine codes. He’d already replaced the fuel pump and a few sensors with no luck. After connecting my scan tool, I noticed intermittent communication drops with the PCM. We swapped in a VIN-programmed module, and the problem vanished instantly. The original PCM’s internal processor was failing under heat load, a common issue I’ve seen in hundreds of these work vans. This simple replacement saved him from chasing phantom problems and got his business moving again.
Is Your Savana Showing These Symptoms?
- ✔ Persistent Check Engine Light (CEL) that won’t clear.
- ✔ Engine stalling, stumbling, or hesitating during acceleration.
- ✔ No-start or hard-to-start conditions, especially when warm.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Diagnostic trouble codes (DTCs) pointing to internal module failure, such as P0601, P0602, or P0606.
- ✔ Loss of communication with the PCM when using a scan tool.
A Straightforward Guide to Installation
Installing your 2005-2007 Savana 3500 PCM is a manageable job for a DIYer with basic tools. Since we program it beforehand, you won’t need a trip to the dealer. Just follow these steps.
- Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent accidental reconnection.
- Locate the PCM: On Savana and Express vans, the PCM is typically located in the engine compartment on the driver’s side, near the firewall.
- Disconnect Connectors: Carefully unclip and remove the electrical wiring harness connectors from the old PCM. These connectors have locking tabs; be gentle to avoid breaking them.
- Remove the Old Module: Unbolt the PCM from its mounting bracket. There are usually a few bolts holding it in place.
- Install the New PCM: Mount your new, pre-programmed PCM onto the bracket and secure it with the bolts.
- Reconnect Everything: Plug the wiring harness connectors firmly into the new module until they click. Reconnect the negative battery terminal.
- Perform Security Relearn: In many cases, you will need to perform a security relearn procedure (often called a Passlock or Passkey relearn) to allow the vehicle to start. This procedure typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Consult your vehicle’s service information for the exact steps.
Verified Vehicle Compatibility
This module is a direct replacement for part numbers 12602801, 12589462, and 89017749. It is confirmed to fit a wide range of GM vehicles, including but not limited to:
- GMC Savana 1500/2500/3500 Van (2005-2007)
- Chevrolet Express 1500/2500/3500 Van (2005-2007)
- Chevrolet Silverado & GMC Sierra 1500/2500/3500 (2005-2007 Classic)
- Chevrolet Suburban 2500 & GMC Yukon XL 2500 (2005-2006)
- Chevrolet Avalanche 2500 (2005-2006)
- GMC Safari & Chevrolet Astro (2005)
- Chevrolet Blazer S10 & GMC Jimmy S15 (2005)
- Cadillac CTS-V (2004-2005, check specific ID)
Please provide your VIN upon purchase to ensure we send you a perfectly matched and programmed module for your specific vehicle configuration.
Frequently Asked Questions
Do I need to do anything after installing this PCM?
Because this module arrives programmed to your VIN, the main step after physical installation is the security relearn procedure. This syncs the new PCM with your vehicle’s anti-theft system and is required for the engine to start.
Is this a plug-and-play part?
It’s as close as it gets. The physical installation is plug-and-play, and the VIN programming is done by us. The only additional step for you is the security relearn, which requires no special tools.
What information do you need from me?
After you place your order, we will need your vehicle’s 17-digit Vehicle Identification Number (VIN). This is crucial for us to load the correct GM-certified software and calibrations for your specific engine, transmission, and options.
Will this fix my check engine light?
If the check engine light is caused by a faulty PCM (e.g., codes P0601, P0606) or a software-related issue that the latest GM updates address, then yes, this will resolve the problem. It will not fix issues caused by other failing sensors or mechanical parts.
Where is the VIN located on my Savana Van?
You can find your VIN on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.