Restore Your Cadillac’s Brain and End Electrical Chaos
If you’re dealing with a 2008-2013 Cadillac CTS that seems to have a mind of its own—flickering lights, malfunctioning power windows or locks, a parasitic battery drain, or random warning messages—the culprit is very likely a failing Body Control Module (BCM). As the central command center for your vehicle’s body electronics, a faulty BCM can cause a cascade of frustrating and unpredictable problems. I’ve seen it countless times in the shop: a beautiful car rendered unreliable by one single component.
Don’t let a bad BCM sideline your Cadillac. This is a direct-replacement Body Control Module, part number 20815898, that solves these issues for good. The best part? We eliminate the biggest headache of this repair. Instead of towing your car to a dealership for expensive diagnostics and programming, we flash this module with the latest GM software specifically for your vehicle’s VIN before we ship it. This streamlines the entire process, saving you significant time and money.
From the Diagnostic Bay
A customer brought in his 2011 CTS, completely fed up. The interior lights would stay on, draining the battery overnight, and the remote key fob worked only intermittently. He’d already replaced the battery twice. A quick scan with my pro-level tool showed a slew of communication errors all pointing back to the BCM. After confirming power and grounds to the module were good, we knew it was internally fried. We installed one of our pre-programmed modules, performed the necessary key relearn and SDM setup, and all the bizarre electrical gremlins vanished. He drove away with a car that felt new again, all for a fraction of the dealership’s quote.
Is Your Cadillac Showing These Symptoms?
A failing BCM can manifest in many ways. If you’re experiencing any of the following, this module is the likely solution:
- ✔ Erratic or non-functional power windows, door locks, or mirrors.
- ✔ Interior or exterior lights that won’t turn on or off.
- ✔ A persistent battery drain that kills your battery overnight.
- ✔ The security or anti-theft system preventing the car from starting.
- ✔ Malfunctioning instrument cluster gauges or warning lights.
- ✔ Remote keyless entry (fob) not working correctly.
- ✔ Communication error codes with other vehicle modules.
A Straightforward Guide to Installation
Replacing the 2008-2013 CTS Body Control Module is a manageable job for a confident DIYer or any professional technician. Our pre-programming service handles the most complex step for you.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait a few minutes before beginning work.
- Locate the BCM: On the 2008-2013 Cadillac CTS, the BCM is typically located in the driver’s side of the passenger compartment, on the left-hand side of the dash, often behind the lower dash panel.
- Remove the Old Module: Carefully disconnect the electrical connectors. They have locking tabs that must be depressed. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Mount your new, pre-programmed BCM and securely reconnect all electrical connectors. Ensure they click into place.
- Reconnect Battery: Re-attach the negative battery terminal.
- Perform Relearn Procedures: This is a CRITICAL step. You will need a capable diagnostic scan tool to perform the ‘Setup SDM Primary Key in BCM’ procedure to ensure the airbag system communicates correctly and to clear any related warning lights. Some vehicles may also require a Brake Pedal Position Sensor recalibration. Failure to perform these steps can result in warning lights and improper system function.
Verified Vehicle Compatibility
This BCM is a direct replacement for a wide range of General Motors vehicles and interchanges with numerous part numbers. Please verify your part number or vehicle in the list below. After purchase, we must have your VIN to program the module correctly.
This module replaces the following part numbers: 10382479, 15093910, 15276271, 15299986, 15819552, 15828601, 15837419, 15872388, 15872421, 15880684, 15921352, 15921353, 15948438, 15948439, 20815898, 20839063, 20864767, 20864768, 20921435, 20921436, 20935349, 22860591, 25826124, 25826125, 25847588, 25847589, 25892622, 25910474, 25934762, 25934763, 95151084
Fits Models Including:
- Cadillac CTS (2008-2013)
- Chevrolet Impala (2006-2013)
- GMC Acadia (2007-2012)
- Chevrolet Traverse (2009-2012)
- Buick Enclave (2008-2012)
- Cadillac DTS (2006-2011)
- And many other GM cars, trucks, and vans. Please check the detailed fitment list at the top of the page.
Frequently Asked Questions
Do I need to get this 2008-2013 CTS Body Control Module programmed?
No! That’s the primary benefit of our service. We program the module to your car’s specific VIN before shipping it. This saves you the time, hassle, and expense of a dealership visit for programming.
What information do you need from me?
After you complete your purchase, you must provide us with your vehicle’s 17-digit VIN (Vehicle Identification Number). We cannot ship the module until we have this information to program it correctly.
Where is the BCM located on my 2010 Cadillac CTS?
On most 2008-2013 CTS models, the BCM is found inside the car on the driver’s side, attached to the dash structure, usually to the left of the steering column and behind the lower trim panel.
Will this fix my airbag light?
A bad BCM can cause an airbag light by disrupting communication with the SDM (Sensing and Diagnostic Module). Replacing the BCM is the first step, but you MUST perform the ‘Setup SDM Primary Key in BCM’ procedure with a scan tool to re-establish this communication and turn off the light.
Is this a difficult part to replace myself?
For someone with moderate mechanical skill, it’s very manageable. The physical swap is straightforward. The most critical part is performing the post-installation electronic relearn procedures, which requires a bi-directional scan tool. If you don’t have one, your local mechanic can typically perform these steps for you quickly.