Restore Your Van’s Reliability and Power
Is your Chevrolet Express van feeling sluggish, throwing a check engine light, or refusing to start reliably? These frustrating issues often point to a failing Powertrain Control Module (PCM), the central computer of your vehicle. Don’t let a faulty module keep your workhorse off the road. This replacement PCM, service number 12635902, is the definitive solution to get your van running like new again. We take the guesswork and hassle out of the repair by pre-programming the unit with the latest GM software, tailored specifically to your vehicle’s VIN. This ensures a seamless installation and restores the precise performance and efficiency you depend on every day.
Warning Signs and How to Overcome Them
A failing PCM can cause a wide range of confusing symptoms. If you’re experiencing any of the following, this module is the solution you need:
- ✔ Persistent Check Engine Light (CEL) that won’t go away.
- ✔ Diagnostic Trouble Codes (DTCs) like P0601, P0602, P0606, or other communication errors.
- ✔ Unexplained drop in fuel economy.
- ✔ Rough idling, stalling, or hesitation during acceleration.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Complete no-start condition where the engine cranks but won’t fire up.
Expert Tip: The Critical First Step
Before you even think about touching the old module, disconnect the negative terminal of your vehicle’s battery and wait at least 30 minutes. This crucial step fully drains any residual power from the system, preventing potential electrical shorts that could damage your new PCM or other sensitive electronics during installation. It’s a simple precaution that ensures a smooth and successful repair.
Guided Installation for a Confident Fix
Installing your new 2008-2009 Express 1500 PCM is a straightforward process. With our pre-programming service, the most complex part is already done for you. Follow these steps to get back on the road:
- Safety First: As mentioned in our tip, disconnect the negative battery terminal and wait 30 minutes.
- Locate the Old PCM: On your Express Van, the PCM is typically found in the engine compartment on the driver’s side, often near the firewall or air filter housing.
- Disconnect Wiring: Carefully release the locking tabs on the electrical harness connectors and gently pull them straight out from the module. Never force them. Inspect the connectors for any corrosion or damaged pins.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. It’s usually held in place by a few small bolts.
- Install the New PCM: Mount your new, pre-programmed module in the same location and secure it with the original bolts.
- Reconnect and Secure: Firmly plug the wiring harnesses back into the new PCM. You should hear a click as they lock into place. Reconnect your battery terminal.
- Perform Relearn Procedure: In many cases, you will need to perform a simple security relearn procedure (often called a Passlock or Passkey relearn) to sync the new PCM with your vehicle’s anti-theft system. This procedure can typically be done without special tools and instructions are widely available online or in your service manual.
Tailored Fit for Your Ride
This module is a direct-fit replacement for a wide range of GM vehicles. While this listing is focused on the 2008-2009 Express 1500 PCM, it is also compatible with the following models and service numbers. Please verify your part number (12597125, 12612397, 12635902, etc.) before ordering.
- AURA 08-09 (2.4L)
- COBALT 07-10 (2.2L, 2.4L)
- EXPRESS 1500 VAN 08-09 (4.3L)
- G5 07-10
- G6 08-10 (2.4L)
- HHR 07-11 (2.2L, 2.4L)
- IMPALA 10-11
- LUCERNE 09-11 (3.9L)
- MALIBU 07-12 (2.2L, 2.4L, 3.5L)
- SAVANA 1500 VAN 08-09 (4.3L)
- SIERRA 1500 PICKUP 07-09 (4.3L)
- SILVERADO 1500 PICKUP 07-09 (4.3L)
- SKY 08-10 (2.4L)
- SOLSTICE 08-10 (2.4L)
- VUE 08-10 (2.4L)
By providing us with your VIN at checkout, you guarantee that you will receive a perfectly matched and updated module, ready to restore your vehicle’s brainpower and give you back that confident, worry-free drive.
Frequently Asked Questions
Do I need to program this computer?
No. The main benefit of our service is that we program the module for you before it ships. Simply provide your vehicle’s VIN during or after checkout, and we’ll flash it with the latest GM software for your specific vehicle, saving you a trip to the dealer.
Where is the PCM located on my 2008-2009 Express 1500?
On the 2008-2009 Express 1500 Van, the PCM is located in the engine compartment on the driver’s side (LH), typically mounted near the rear of the engine bay.
What is a security or CASE relearn procedure?
After installation, your vehicle’s anti-theft system needs to synchronize with the new PCM. This is done via a security relearn. Additionally, a CASE (Crankshaft Position System Variation) relearn may be needed to ensure the engine runs smoothly and doesn’t set a misfire code. The security relearn can often be done at home, while the CASE relearn typically requires a capable scan tool.
Is this a simple plug-and-play installation?
It’s very close. Because we handle the programming, the physical installation is simple plug-and-play. However, the post-installation electronic ‘relearn’ procedures are a necessary final step for most vehicles to ensure full functionality.
What information do you need from me to program the module?
All we need is your vehicle’s 17-digit Vehicle Identification Number (VIN). You can provide this in the notes at checkout or send it to us in a message after your purchase. This ensures a perfect software match.