Is Your Chevy Express Van Running Rough? The PCM Might Be the Culprit.
If your 2005, 2006, or 2007 Chevrolet Express 3500 is suffering from perplexing issues like a persistent check engine light, erratic shifting, poor fuel economy, or even a no-start condition, the problem may lie with its central nervous system: the Powertrain Control Module (PCM). This vital component manages everything from fuel injection and ignition timing to transmission shift points and emissions controls. When it fails, it can cause a wide range of symptoms that can be difficult to diagnose, leaving you stranded and frustrated.
Don’t let a faulty computer sideline your workhorse. This is a direct-fit replacement Powertrain Control Module, part number 89017749, engineered to restore your van’s original performance and reliability. The best part? We eliminate the most significant hassle of PCM replacement. We will program the module specifically for your vehicle using your VIN before it ever leaves our facility. This means it arrives at your door with the latest GM software updates, ready for a straightforward installation without requiring an expensive trip to the dealership for programming.
I remember a customer with an ’06 Express 3500 work van that was brought in on a tow truck. The complaint was ‘cranks but won’t start.’ The previous shop had replaced the fuel pump and the crankshaft position sensor, but the problem persisted. After hooking up our scan tool, we noticed an intermittent loss of communication with the PCM. A visual inspection of the module, located in the LH rear of the engine compartment, revealed slight corrosion on one of the connectors from moisture intrusion. We swapped in a known-good, programmed PCM, and the van fired right up. It’s a classic case where chasing individual symptoms can be costly; sometimes, you have to go straight to the brain of the operation.
Signs You Need a 2005-2007 Express 3500 PCM Replacement
A failing PCM can manifest in numerous ways, often mimicking other component failures. If you’re experiencing several of the following symptoms, it’s a strong indicator that your vehicle’s computer needs attention.
- ✔ Illuminated Check Engine Light: Often the first sign, with codes related to module communication, sensor circuits, or processor faults.
- ✔ Engine Performance Issues: Stalling, rough idling, hesitation during acceleration, or a noticeable loss of power.
- ✔ Poor Fuel Economy: If the PCM can’t properly manage the air-fuel mixture, your van’s MPG will suffer.
- ✔ Transmission Shifting Problems: Harsh shifting, delayed engagement, or getting stuck in one gear (limp mode).
- ✔ No-Start Condition: The engine may crank over but fail to start if the PCM isn’t commanding the fuel injectors or ignition coils to fire.
- ✔ Intermittent Electrical Gremlins: Seemingly random issues that come and go can sometimes be traced back to a failing computer.
The VIN Programming Advantage
Ordering a PCM online can be a gamble if it isn’t properly prepared. An unprogrammed module is just a metal box. Our process ensures success. When you place your order, you provide us with your van’s 17-digit Vehicle Identification Number (VIN). Our technicians use this VIN to load the exact GM-specified software and calibrations for your vehicle’s specific engine, transmission, and options. This critical step ensures all systems communicate correctly, giving you a plug-and-play solution that restores factory function. In many cases, a simple security relearn procedure is all that’s needed to get back on the road.
Guaranteed Fitment for Your GM Vehicle
This module, also known by part numbers 12589462 and 12602801, is a direct replacement for a wide range of GM trucks and vans. Please verify your vehicle is on the list below to ensure compatibility.
This part will fit these makes and models with these options:
- AVALANCHE 2500 05-06 Electronic Control Module; (LH front under battery)
- ASTRO 05 Electronic Control Module; (LH front by battery)
- BLAZER S10/JIMMY S15 05 Electronic Control Module; (RH front engine compartment)
- CTS 04-05 Electronic Control Module; (RH engine compartment), V-Series
- EXPRESS 1500 VAN 05-07 Electronic Control Module; (LH rear engine compartment)
- EXPRESS 2500 VAN 05-07 Electronic Control Module; (LH rear engine compartment), gasoline
- EXPRESS 3500 VAN 05-07 Electronic Control Module; (LH rear engine compartment), gasoline
- SAFARI (GMC) 05 Electronic Control Module; (LH front by battery)
- SAVANA 1500 VAN 05-07 Electronic Control Module; (LH rear engine compartment)
- SAVANA 2500 VAN 05-07 Electronic Control Module; (LH rear engine compartment), gasoline
- SAVANA 3500 VAN 05-07 Electronic Control Module; (LH rear engine compartment), gasoline
- SIERRA 1500 PICKUP 05-07 (classic style) Electronic Control Module; w/o hybrid, w/4.3L
- SIERRA 2500 PICKUP 05-07 (classic style) Electronic Control Module; gasoline, 8.1L
- SIERRA 3500 PICKUP 05-07 (classic style) Electronic Control Module; gasoline, 8.1L
- SILVERADO 1500 PICKUP 05-07 (classic style) Electronic Control Module; w/o hybrid, w/4.3L
- SILVERADO 2500 PICKUP 05-07 (classic style) Electronic Control Module; gasoline, 8.1L
- SILVERADO 3500 PICKUP 05-07 (classic style) Electronic Control Module; gasoline, 8.1L
- SUBURBAN 2500 05-06 Electronic Control Module; (LH front under battery), 8.1L
- YUKON XL 2500 05-06 Electronic Control Module; (LH front under battery), 8.1L
Frequently Asked Questions
Do I need to have this module programmed?
No. We handle the programming for you before shipment. Simply provide your vehicle’s VIN during checkout, and the module will arrive with the correct software for your specific vehicle, ready for installation.
Where is the PCM located on my 2005-2007 Express Van?
On the Express and Savana vans from this era, the PCM is typically located in the engine compartment, on the left-hand (driver’s) side, towards the rear of the compartment.
Will I need to perform a security relearn procedure?
Yes, in most cases, you will need to perform a simple security relearn procedure after installation. This allows the new PCM to communicate with your vehicle’s anti-theft system. The procedure is straightforward and typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating this cycle three times. Instructions are readily available online for your specific model.
Is this a new or used part?
This is a high-quality, tested, and verified genuine OEM part that has been inspected to ensure it meets or exceeds original factory specifications. It is programmed with the latest software for optimal performance.
What if my part number is slightly different?
This module, 89017749, is the correct service replacement for several original part numbers, including 12589462 and 12602801. As long as your vehicle is on the compatibility list, this module will function correctly once programmed to your VIN.