Dealing with erratic engine behavior, a persistent check engine light, or a no-start condition in your Cadillac can be incredibly frustrating. As a technician with over two decades of experience, I’ve seen firsthand how a failing Engine Control Module (ECM) can disrupt your vehicle’s entire performance. The ECM is the central computer of your engine, and when it malfunctions, it can cause a cascade of confusing and costly problems. This isn’t just a part; it’s the solution to restoring your vehicle’s reliability and getting you back on the road with confidence.
This is a direct-fit replacement Engine Control Module, part number 12603530, for your 2006 XLR Engine Control Module and a wide range of other GM vehicles. The biggest hurdle with ECM replacement has always been the expensive and time-consuming programming required. We eliminate that problem entirely. Before we ship this module, our experts will program it with the latest official GM software updates, using your vehicle’s specific VIN. This means it arrives at your door ready for a simple, plug-and-play installation.
From the Diagnostic Bay: The Ghost in the Machine
I remember a 2006 Cadillac CTS-V (which uses this exact module) that came into the shop with a list of bizarre, intermittent issues. The owner reported random stalling at stoplights, occasional hard shifting, and a check engine light that would come and go. His previous mechanic had replaced a few sensors without success. On my scan tool, I saw a few communication codes (U-codes) and a history code for P0601 (Internal Control Module Memory Check Sum Error). This P-code is a dead giveaway. The ECM’s internal processor was failing. We installed one of our pre-programmed modules, and the car ran perfectly. It’s a classic case where chasing individual symptoms is futile; the core problem was the vehicle’s brain.
Is Your Vehicle Showing These Symptoms?
A faulty ECM can manifest in many ways. If you’re experiencing any of the following, a failing engine computer could be the culprit:
- ✔ Persistent Check Engine Light (CEL) that won’t clear
- ✔ Engine stalling, stuttering, or misfiring
- ✔ Vehicle won’t start, but the battery and starter are good
- ✔ Poor fuel economy and noticeable loss of power
- ✔ Unexplained transmission shifting problems
- ✔ Failure to pass emissions testing
- ✔ Diagnostic trouble codes (DTCs) like P0601, P0606, or U0100
A Straightforward Guide to Installation
Installing your new 2006 XLR Engine Control Module is a manageable task for a confident DIYer. Since we handle the programming, you won’t need any special scan tools for the setup.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the ECM: On the 2006 XLR, the ECM is typically found in the engine compartment on the right-hand (passenger) side. Consult a service manual for your specific vehicle if you’re unsure.
- Disconnect the Connectors: Carefully unclip the wiring harness connectors from the old module. These connectors have locking tabs that need to be released before pulling. Avoid forcing them.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware, as you may need it for the new installation.
- Install the New Module: Mount your new, pre-programmed ECM in place and secure it with the original bolts.
- Reconnect Everything: Firmly plug the wiring harnesses into the new module until they click into place. Reconnect the negative battery terminal.
- Perform Relearn (If Necessary): While the core programming is done, some vehicles require a security or crank-position sensor relearn procedure. This can often be done without special tools (e.g., by cycling the key). Check your service manual for any specific vehicle-relearn steps.
Verified Vehicle Compatibility
This module, part number 12603530, is a direct replacement for several service numbers, including 12590032, 12602044, 12605843, and more. It fits a vast array of GM vehicles. Please verify your exact model and options below. The primary fitment is for the 2006 XLR Engine Control Module, but it is compatible with many others.
BUICK ALLURE 08-09, ENCLAVE 08, LACROSSE 08-09, LUCERNE 06/08, RAINIER 07
CHEVROLET COBALT 06, COLORADO 08, HHR 06, IMPALA 06/08-09, MALIBU 06/08-10, MONTE CARLO 06, TRAILBLAZER 07-09, UPLANDER 06/08-09
GMC ACADIA 07-08, CANYON 08, ENVOY 07-09
HUMMER H3 08
ISUZU ASCENDER 08, I-290 08, I-370 08
PONTIAC G6 06-09, GRAND PRIX 08, PURSUIT 06, SOLSTICE 06
SAAB 9-7X 07-08
SATURN AURA 08-09, ION 06, OUTLOOK 08, RELAY 06, TERRAZA 06, VUE 08-10
(Note: This is a partial list. Please use the fitment checker or contact us with your VIN to confirm.)
Do I need to do any programming myself?
Do I need to do any programming myself?
No. We handle all the necessary programming before shipment. We will flash the module with the latest GM software updates using the VIN you provide, making it a plug-and-play solution for your vehicle.
How do I provide my VIN?
After you complete your purchase, you will need to send us your 17-digit Vehicle Identification Number (VIN). You can typically add it as a note during checkout or reply to your order confirmation email. We cannot ship the part until we receive your VIN.
Is this a new or used part?
This is a high-quality, fully tested, and guaranteed recycled OEM part. Each module is inspected and programmed by our expert technicians to ensure it meets or exceeds original factory performance standards.
What if my original part number is different?
This module is interchangeable with several part numbers, including 12590032, 12602044, 12605843, 12607096, 12630457, and 19210737. As long as your vehicle is on our compatibility list, this module will function correctly, and it will be programmed specifically for your car.
Will this fix my car’s specific problem?
This ECM will correct issues directly caused by a faulty engine computer. While the symptoms we’ve listed are common indicators of ECM failure, we always recommend a proper diagnosis by a qualified mechanic to confirm the ECM is the root cause before ordering.