Is Your Work Van Unreliable? Get Back on the Road Fast.
As a mechanic with over two decades of experience, I know that for a Savana 3500 owner, downtime isn’t just an inconvenienceโit’s lost income. If you’re dealing with frustrating issues like unexplained stalling at intersections, a persistent check engine light with a host of confusing codes, poor fuel mileage, or a complete no-start condition, the problem often points to the very brain of your engine: the Engine Control Module (ECM).
Just last month, a local contractor brought in his 2018 Savana 3500. It was randomly dying in traffic and wouldn’t communicate properly with our scan tool. After confirming the wiring harness and power/ground circuits were solid, we identified a faulty ECM. Swapping in a pre-programmed module like this one had his van running reliably by the next morning, saving him from another day of canceled jobs.
The Smart Solution: A VIN-Programmed 2018 Savana 3500 ECM
Forget the hassle and high cost of a dealership visit. This ECM, part number 12704475, is the definitive solution. We take the guesswork out of the repair by programming the module specifically to your vehicle’s VIN before it ships. This ensures it has the latest, most stable software updates from GM, tailored to your van’s exact specifications. It’s the key to restoring original performance and reliability.
- โ VIN-Specific Programming: We flash the module with your vehicle’s VIN, ensuring it works seamlessly with your existing systems.
- โ Latest GM Calibrations: Your ECM arrives with the newest software updates to optimize engine performance and efficiency.
- โ Direct Replacement: This module is a direct fit for original part numbers 12704475, 12692069, 12680656, 12686383, and 12688528.
- โ Solves Common Failures: Effectively corrects issues like harsh shifting, no-start conditions, random stalling, and false sensor codes.
Expert Pro Tip: Check for the Root Cause
Before installing your new ECM, I always recommend a quick inspection of the vehicle’s charging system. A failing alternator that produces voltage spikes is a common cause of ECM failure. Simply check the battery voltage with the engine running; it should be stable, typically between 13.8 and 14.5 volts. Verifying this can prevent damage to your new investment and save you from a repeat failure down the road.
Installation and Setup Guide
Installing your new ECM is straightforward. However, please read the following steps carefully, especially regarding the post-installation procedures.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the ECM: On the 2018 Savana 3500, the ECM is typically found in the left-hand rear of the engine compartment.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs that must be released. Then, unbolt the old module from its mounting bracket.
- Install the New Module: Bolt the new ECM into place and securely reconnect the electrical connectors. Ensure they click into place.
- Reconnect Battery: Reattach the negative battery terminal.
IMPORTANT: Post-Installation Relearn Procedures
This is a critical step. Because the ECM is tied to your vehicle’s security system, a Vehicle Theft Deterrent System Relearn is often required. If the van cranks but does not start after installation, this procedure must be performed by a qualified technician using a GM-specific programming tool (like Tis2web or Techline Connect). This is not a defect in the part; it’s a standard security feature of modern GM vehicles.
Additionally, other procedures like a Crankshaft Position Variation Relearn or injector flow rate programming may be necessary depending on your vehicle’s specific configuration. The responsibility for performing these relearn and setup procedures lies with the installer.
Verified Vehicle Fitment
This module is compatible with a wide range of GM vehicles. Please verify your model and options below. The ID number, if listed, can be found on the sticker of your original part.
- Cadillac Escalade / ESV: 2018
- Cadillac XTS: 2018 (3.6L, VIN 8)
- Chevrolet Corvette: 2018-2019 (LT1 & LT4 engines)
- Chevrolet Express 2500 / 3500 Van: 2018 (4.3L)
- Chevrolet Silverado 1500: 2018 (ID 12680656)
- Chevrolet Suburban 1500: 2018
- Chevrolet Tahoe: 2018
- GMC Savana 2500 / 3500 Van: 2018 (4.3L)
- GMC Sierra 1500 / Denali 1500: 2018 (ID 12680656 or 12686383)
- GMC Yukon / Yukon XL 1500: 2018