Restore Your Buick’s Performance and Reliability
Is your Buick Rendezvous acting up? Experiencing a persistent Check Engine Light, rough idling, stalling, or unpredictable shifting? These are classic signs of a failing Engine Control Module (ECM), the computer that serves as your vehicle’s brain. Driving with a faulty ECM isn’t just frustrating; it can lead to poor fuel economy, failed emissions tests, and even leave you stranded. For over 20 years in the shop, I’ve seen how a bad engine computer can cause a cascade of issues that are often misdiagnosed, costing owners time and money on unnecessary repairs.
This isn’t just a replacement part; it’s a complete, hassle-free solution. We are offering a genuine, used GM Engine Control Module (Part No. 12592124) that has been meticulously tested and is ready for installation. The most significant benefit? We program it specifically for your vehicle using your VIN before it ships. This means it arrives loaded with the latest GM software updates, eliminating the need for an expensive trip to the dealership for programming. You get a reliable part that’s truly plug-and-play.
From the Diagnostic Bay: A Rendezvous Riddle
A customer brought in a 2005 Rendezvous with a complaint that stumped two other shops: it would randomly stall at stoplights, but only after it was fully warmed up. There were no consistent trouble codes, just a history of random misfires. We checked fuel pressure, scanned for vacuum leaks, and tested sensors—all were within spec. My gut told me it was electronic. On a hunch, I monitored the ECM’s data stream during a long test drive. Just as the engine stalled, I saw the short-term fuel trim values go haywire. The ECM’s internal processor was failing under heat soak. We swapped in a pre-programmed ECM just like this one, and the problem was solved instantly. It’s a perfect example of how a faulty 2004-2006 Rendezvous ECM can create phantom issues that defy typical diagnostics.
Common Signs of a Failing ECM
- ✔ Check Engine Light is on, often with internal processor codes like P0601 or P0606.
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained drops in fuel efficiency.
- ✔ The vehicle stalls intermittently, especially when warm.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Noticeable loss of power and poor acceleration.
- ✔ Communication errors with diagnostic scan tools.
A Straightforward Guide to Installation
Installing your programmed 2004-2006 Rendezvous ECM is a job most DIYers can handle in under an hour with basic hand tools. This module is typically located in the engine compartment on the driver’s side (LH).
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait 10-15 minutes to allow capacitors to discharge.
- Locate the ECM: On the Rendezvous, it’s usually found in the engine bay, often near the firewall or air filter housing.
- Disconnect the Wiring: Carefully unplug the electrical connectors. Most have a locking tab or lever that needs to be released. Never force them.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket.
- Install the New Module: Bolt your new, pre-programmed ECM into place.
- Reconnect Everything: Plug the wiring harnesses back into the new module until they click securely. Reconnect the negative battery terminal.
- Final Step: Your vehicle may require a security relearn procedure, which is a simple process you can typically do yourself. Instructions are widely available online or in your owner’s manual.
Verified Vehicle Compatibility
This module, service number 12592124, is a direct replacement for service numbers 12581144, 12588472, and 19260507. It is guaranteed to fit the following vehicles:
Buick LaCrosse: 2005-2008 (3.6L)
Buick Rendezvous: 2004-2005 (with ID 19260507)
Buick Rendezvous: 2006 (3.6L)
Cadillac CTS: 2004 (Base, with ID 19260507)
Cadillac CTS: 2004-2006 (Base, with ID 12592124)
Cadillac CTS: 2007 (Base)
Cadillac SRX: 2004-2006 (3.6L)
Your Solution to a Frustrating Problem
Don’t let a bad computer keep your vehicle off the road. This reliable, tested, and pre-programmed 2004-2006 Rendezvous ECM is the most efficient and economical way to restore your vehicle’s engine performance and get back to driving with confidence. Simply provide your VIN at checkout, and we’ll handle the rest.
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to program the ECM with the exact software and calibrations for your vehicle’s specific options. This ensures perfect compatibility and function right out of the box, avoiding a trip to the dealer.
Is this a new part?
No, this is a high-quality, genuine GM part sourced from a salvaged vehicle. Each unit is inspected and tested to ensure it meets our strict quality standards before being programmed and shipped.
Will I need to do anything after installation?
In most cases, the module is plug-and-play. Some GM vehicles may require a simple security relearn procedure (often called a Passlock or Passkey relearn) to sync the module with your keys. This can typically be done in your driveway without special tools.
What if this doesn’t fix my problem?
While this module fixes the common issues listed, we always recommend a proper diagnosis from a qualified technician. Vehicle electronics are complex, and other parts can cause similar symptoms. We guarantee the module is functional and programmed correctly.
Are the compatible part numbers interchangeable?
Yes. This ECM (12592124) is a direct, updated replacement for service numbers 12581144, 12588472, and 19260507. If your original module has one of these numbers, this part will work for you.