Is Your GM Vehicle Running Rough, Stalling, or Showing a Check Engine Light?
If you’re dealing with baffling electrical gremlins, poor fuel economy, or a vehicle that just won’t start, a failing Engine Control Module (ECM) is often the culprit. In my 20+ years as a diagnostic technician, I’ve seen firsthand how a faulty ECM can mimic a dozen other problems, leading to wasted time and money on unnecessary parts. A customer’s 2009 Trailblazer with the 6.0L came in last month with intermittent stalling and a host of communication codes. After confirming the wiring and sensors were sound, we traced the issue to an internal failure in the original ECM. This module was the exact solution.
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We take a genuine GM ECM and professionally program it with the latest official software updates using your vehicle’s unique VIN. This means it arrives at your door ready for a true plug-and-play installation, saving you a costly trip to the dealership and the hassle of arranging a tow.
Common Symptoms of a Failing GM ECM:
If you’re experiencing any of the following, your ECM may be at the end of its service life:
- โ Persistent Check Engine Light (CEL) with various communication or processor codes.
- โ Engine stalling, misfiring, or running erratically.
- โ Complete no-start condition where the engine cranks but won’t fire up.
- โ Poor or inconsistent automatic transmission shifting.
- โ Loss of power and decreased fuel efficiency.
- โ Communication issues with diagnostic scan tools.
Expert Pro Tip: Protect Your New Module
Before installing your new ECM, take a moment to inspect the ignition coils and their wiring harnesses. A common cause of ECM driver failure on these GM platforms is a shorted ignition coil sending excessive voltage back to the computer. A quick visual inspection for cracks, burns, or corrosion on the coils and connectors can prevent you from damaging your new module and having to do the job twice.
Plug-and-Play Installation: No Dealer Visit Required
Installing your pre-programmed module is a straightforward process you can do at home. For the 2009 Envoy Engine Module, you’ll find it located on the driver’s side of the engine.
- Safety First: Always disconnect the negative battery terminal and wait 10-15 minutes for any residual power to dissipate.
- Locate the ECM: On the 2009 Envoy 5.3L, it’s typically mounted on the left-hand (driver’s) side of the engine. Other models like the Colorado/Canyon have it on the RH firewall.
- Disconnect Connectors: Carefully release the locking tabs on the wiring harness connectors and pull them straight out. Never force them. Inspect the pins for any corrosion or damage.
- Remove the Module: Unbolt the old ECM from its mounting bracket.
- Install the New ECM: Mount your new module, reconnect the wiring harnesses until they click securely in place, and re-fasten the locking tabs.
- Reconnect Battery: Reattach the negative battery terminal. Your vehicle is now ready to start with the latest GM software.
Guaranteed Compatibility for Your Vehicle
This ECM is a direct replacement for a wide range of GM vehicles. Please provide your VIN at checkout to ensure we load the correct software for your specific application. This module is interchangeable with the following service part numbers:
Part Numbers: 12636659, 12639300, 1263605, 12628993, 12628911, 12625453, 12622175, 12630464, 12678512
This part will fit these makes and models with these options:
- CANYON 09-12 (2.9L, 3.7L)
- COLORADO 09-12 (2.9L, 3.7L)
- CORVETTE 09 (ZR1)
- CTS 09 (6.2L)
- DTS 09-11
- ENVOY 09 (5.3L)
- HUMMER H3 09-10 (3.7L)
- LUCERNE 09-11 (4.6L)
- SAAB 9-7X 09
- SRX 09 (4.6L)
- STS 09-10 (4.4L, 4.6L)
- TRAILBLAZER 09 (6.0L)
- XLR 09
Don’t let a faulty computer keep you off the road. Order today and restore your vehicle’s performance and reliability with a solution that’s programmed specifically for you.