Restore Peak Performance to Your Cadillac
Is your 2005-2007 Cadillac STS or 2005 CTS suffering from perplexing issues like a persistent check engine light, erratic engine behavior, stalling, or a complete no-start condition? These are often hallmark signs of a failing Powertrain Control Module (PCM), the central computer of your vehicle’s engine management system. A faulty PCM can disrupt everything from fuel delivery and ignition timing to transmission shifting, leaving you with an unreliable and frustrating driving experience. This replacement PCM, part number 12600940, is the definitive solution to restore your Cadillac’s original performance and reliability.
From the Diagnostic Bay
We had a 2006 STS 3.6L towed in that was a real head-scratcher. It would crank but never start, and there were no clear trouble codes pointing to a single sensor. The owner had already replaced the crank and cam sensors with no luck. After verifying fuel pressure and spark, we hooked up our scope to the injector control signals coming from the PCM and found they were erratic and weak. We suspected the PCM’s driver circuit had failed internally. We installed one of our pre-programmed modules, performed the security relearn, and the engine fired up on the first try. It’s a classic case where a simple component swap, when it’s the right one, solves a complex problem and saves the owner from endless diagnostic bills.
Common Symptoms of a Failing Cadillac PCM
- ✔ Persistent Check Engine Light (CEL) with various communication or performance codes.
- ✔ Unexplained stalling or engine shutting off while driving.
- ✔ Rough idling or engine misfires.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Engine cranks but refuses to start.
- ✔ Failure to pass state emissions tests.
The Plug-and-Play Solution: Your 2005-2007 STS PCM
Don’t let a faulty computer keep your luxury vehicle off the road. We take the guesswork and high dealership costs out of the equation. This isn’t just a part in a box; it’s a comprehensive solution. When you order, you provide us with your vehicle’s 17-digit Vehicle Identification Number (VIN). Our technicians then use that VIN to flash the module with the latest, most stable software updates directly from GM. This ensures perfect compatibility with your vehicle’s specific configuration and options. The 2005-2007 STS PCM arrives at your door ready for installation, eliminating the need for an expensive trip to the dealer for programming.
Located in the right-hand side of the engine compartment, this module is a direct-fit replacement for the original unit, ensuring a straightforward installation. Once installed, a simple security relearn procedure (often called an anti-theft relearn) is typically all that’s needed to synchronize the new module with your car’s keys and security system. This procedure can usually be done in your own driveway without special tools.
This Part Fits:
- 2005-2007 Cadillac STS with 3.6L Engine
- 2005 Cadillac CTS (Base Model, ID 12585814)
This module replaces part numbers: 12600940, 12585814, YHTZ. Please verify your part number or contact us with your VIN to ensure compatibility.
Frequently Asked Questions
Do I need to get this PCM programmed by a dealer?
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 the PCM will arrive ready to be installed.
What information do you need from me?
We require your vehicle’s 17-digit Vehicle Identification Number (VIN). This is critical to ensure we load the correct GM-certified software for your car’s specific engine, transmission, and options.
Where is the PCM located on my 2006 Cadillac STS?
The Powertrain Control Module is located in the engine bay, on the right-hand (passenger) side. It is typically a silver metal box with several large electrical connectors.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the original PCM, then this replacement part will solve the issue. However, if the light is on due to a faulty sensor or other component, that issue will still need to be addressed separately.
Is a security or anti-theft relearn procedure required?
Yes, in most cases you will need to perform a security relearn procedure after installation. This syncs the new PCM with your vehicle’s anti-theft system and keys. This is a simple procedure that typically takes 10-30 minutes and does not require any special tools. We can provide instructions upon request.