Signs of a Failing BCM - Module Experts

The Body Control Module (BCM) could be considered a central organizational module for your vehicle. It streamlines the manufacturing and troubleshooting aspects of electronic modules by housing the modules into one, central unit instead of each function having its own device. It also coordinates the operating functions of many non-engine related ancillary items as well as security features. If your BCM begins to malfunction, you will notice a negative effect on the operation of the various parts that the Body Control Module commands and it’s likely that you’ll experience one or more of the following symptoms:

The Intermittent Operation of Electronic Components

Electronic components such as Exterior and Interior Lamps, Chime Warning, Courtesy Lamps, Dome Lamps, Door Ajar Status, Fog Lamps, Wiper Controls, Low and High Beam Head Lamps, Horn, Park Lamps, Central Locking, Horn Chirp, Instrumentation Lighting and Gauges, Speedometer, Odometer, Radio, Power Door Locks, Power Windows, Radio functions etc. In certain instances, these items may not operate at all.

Security Function Errors

Security functions including Remote Keyless Entry (RKE), Vehicle Anti-Theft Security System (VTSS), Passive Anti-Theft System (PATS), (PASSKEY), issues typically are related to Body Control Module failure.

Check Engine Light (CEL) or Other Instrumentation Cluster Warning Lights

A malfunctioning BCM will activate dashboard instrumentation cluster error and warning lights. These lights may flash off and on if the BCM is not able to read the sensors correctly. Your vehicle performance may also be affected as the BCM communicates with other control modules in the vehicle.

Battery Drain (Parasitic drain)

Parasitic drain is due to components in your vehicle continuing to run after the key is turned off. Some parasitic drain is normal – your battery delivers enough energy to keep things like your clock, your radio presets and your security alarm operational. Sometimes, parasitic drain exceeds what is normal, and can cause car battery drain.

No Start Condition

Because of the BCM’s communications with other modules and components you may experience a no crank or no start condition.

In many cases, your BCM will alert you to issues with symptoms, warning lights or both. The key is to heed these warning signs, take prompt action and seek help. Avoiding these warning signs or delaying taking action could cause further vehicle damage, or even a system-wide failure. BCM problems can also mask issues with other modules in your vehicle.


ModuleExperts brings more than 100 years of combined experience in module diagnostics and repairs on all types of control modules including BCM’s. In many instances, ModuleExperts can repair your BCM. In the event your BCM is beyond repair, we maintain an extensive inventory of new and remanufactured control modules to get you up and running quickly. Our A+ BBB rating proves our commitment to first-class customer service and satisfaction. Contact us today to learn more about how we can help service your control module needs.