Restore Your Van’s Performance with a VIN-Programmed ECM
Is your 2016 Chevrolet Express 3500 Van suddenly stalling, refusing to start, or throwing a check engine light that won’t go away? A failing Engine Control Module (ECM) is often the culprit behind these frustrating and costly issues. As a technician with over two decades of experience, I’ve seen firsthand how a faulty ECM can bring a reliable workhorse to a dead stop. This isn’t just an inconvenience; for a work van, it’s lost time and lost income. This replacement ECM, part number 12670335, is the direct, reliable solution to get you back on the road and back to business.
The biggest hurdle in replacing a modern engine computer is the programming. This module completely eliminates that problem. Before we ship it, we flash it with the latest official GM software, specifically matched to your van’s unique Vehicle Identification Number (VIN). This ensures seamless communication between all your vehicle’s systems, from the engine and transmission to the anti-lock brakes. You get a component that’s truly ready for installation, saving you a costly trip to the dealership and the hassle of coordinating programming services. For any professional mechanic or dedicated DIYer, this is the most efficient way to solve complex electronic issues and restore peak performance to your 2016 Express 3500 Van ECM.
Case Study: A Tricky Diagnosis
A few months back, a 2016 Express 6.0L was towed into my shop with an intermittent no-start condition. The owner, a plumber, was losing jobs every day the van was down. It had been to two other shops that couldn’t find the issue because it would start fine for them. When I hooked up my scanner, I found a series of U-codes (communication faults) and a P0601 (Internal Control Module Memory Check Sum Error). These codes pointed directly to an internal failure of the ECM. The old module was simply unreliable. We ordered a VIN-programmed unit just like this one, performed the quick security relearn, and the van fired up instantly. The customer was back on the road the next day, a testament to how a pre-programmed module can be the fastest path to a reliable repair.
Is Your Express Van Showing These Signs?
A failing engine computer can manifest in various ways. If you’re experiencing any of the following, a faulty ECM could be the root cause:
- ✔ Unexplained Check Engine Light (CEL) with codes like P0601, P0606, or U0100.
- ✔ Engine stalling or shutting off randomly while driving.
- ✔ Complete no-start or intermittent starting problems.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Misfire codes that persist even after replacing plugs and coils.
A Straightforward Guide to Your ECM Swap
Installing your new 2016 Express 3500 Van ECM is a manageable job for a DIYer with basic tools. Following the correct procedure is key to a successful installation.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the ECM: On the 2016 Express Van, the ECM is typically found in the engine compartment on the driver’s side, near the firewall or inner fender.
- Disconnect the Harnesses: Carefully release the locking tabs on the electrical connectors and pull them straight out from the module. Never force them. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware as you will reuse it.
- Install the New Module: Mount your new, pre-programmed ECM and securely tighten the bolts. Reconnect the electrical harnesses, ensuring they click firmly into place.
- Reconnect the Battery: Reattach the negative battery terminal.
- Perform Security Relearn: You will likely 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 ECM to sync with your vehicle’s anti-theft system. Consult your vehicle’s service information for the exact procedure.
Verified Vehicle Compatibility List
This ECM is a direct-fit replacement for a wide range of GM vehicles, provided it is programmed for your specific VIN. It is compatible with multiple part numbers including 12668866, 12668994, 12643636, 12663405, 12670335, 22819494, and 12692200. Please confirm your vehicle is on this list:
- Chevrolet Express 2500/3500 Van (2016): 4.8L & 6.0L Engines
- GMC Savana 2500/3500 Van (2016): 4.8L & 6.0L Engines
- Chevrolet Silverado 2500/3500 (2012-2016): 6.0L Engine
- GMC Sierra 2500/3500 & Denali (2012-2016): 6.0L Engine
- Chevrolet Suburban 3500 (2016)
- Chevrolet Cruze (2012-2016)
- Chevrolet Sonic (2012-2016)
- Chevrolet Trax (2013-2016)
- Chevrolet Spark (2014-2015)
- Chevrolet Volt (2011-2015)
- Cadillac ELR (2014-2016)
- Buick Encore (2013-2016)
This is a comprehensive but not exhaustive list. The critical step is providing your VIN so we can ensure the 2016 Express 3500 Van ECM receives the correct software for your exact configuration.
Do I need to do anything after I buy it?
Do I need to do anything after I buy it?
Yes. After your purchase, you MUST send us your vehicle’s 17-digit VIN. We cannot program and ship the module without it. This ensures the ECM is loaded with the correct software for your van’s specific engine, transmission, and options.
Is this a plug-and-play part?
Do I need to do anything after I buy it?
Yes. After your purchase, you MUST send us your vehicle’s 17-digit VIN. We cannot program and ship the module without it. This ensures the ECM is loaded with the correct software for your van’s specific engine, transmission, and options.
Will this fix my transmission shifting problems?
Do I need to do anything after I buy it?
Yes. After your purchase, you MUST send us your vehicle’s 17-digit VIN. We cannot program and ship the module without it. This ensures the ECM is loaded with the correct software for your van’s specific engine, transmission, and options.
What’s the difference between an ECM and a PCM?
Do I need to do anything after I buy it?
Yes. After your purchase, you MUST send us your vehicle’s 17-digit VIN. We cannot program and ship the module without it. This ensures the ECM is loaded with the correct software for your van’s specific engine, transmission, and options.
Does this part come with a warranty?
Do I need to do anything after I buy it?
Yes. After your purchase, you MUST send us your vehicle’s 17-digit VIN. We cannot program and ship the module without it. This ensures the ECM is loaded with the correct software for your van’s specific engine, transmission, and options.