Having a bad body control module in your car can be a serious problem. This small but complex part of an automobile is responsible for controlling key systems that keep the car running, such as locks, windows, lights, and more. It can cause significant issues in the way your vehicle operates and leave you feeling frustrated, especially if you don’t know what the issue is or how to fix it. Fortunately, understanding the causes, symptoms, and repair/replacement cost of a bad body control module can help you identify and address any problems that may arise.
In this blog post, we’ll take a closer look at bad body control modules and discuss the causes and symptoms associated with them as well as the repair/replacement cost you should expect to pay if you need to get a new one installed. By exploring these topics in detail, we hope to provide readers with a better understanding of what they can do if they ever find themselves dealing with this issue in their own vehicles.
What is a Body Control Module?
A Body Control Module (BCM) is an important part of any vehicle’s system. It is an electronic driver that provides control over a variety of body-related functions. The exact capabilities of the BCM vary depending on the type and model of a vehicle, but in general, it oversees wiper, lighting, heating, air-conditioning, and anti-theft systems.

The BCM also communicates with other control modules in order to further enhance the integration of the various systems within the car and ensure smooth operation. This allows drivers to enjoy their vehicles without having to worry about issues arising from incompatible components or ineffective communication between them.
For example, when you turn on the headlights of your car, this action is relayed to your BCM which then sends signals to other related components like your headlight circuit and dimmer switch so that it can properly adjust for dipping or brightening the lights as needed.
Similarly, when you start up your engine on a cold day, your BCM works together with other parts like your heater control module to make sure that your climate control system is ready before you even sit down in the driver’s seat.
Where is a Body Control Module Located?
The body control module (BCM) is a component in vehicles that provides control and coordination for various body systems. It is typically located beneath the dashboard on the majority of models, though the exact side (driver or passenger) can vary from make to make.

In some cases, accessing the BCM may involve partial disassembly of the dashboard and adjacent trim. However, this process is usually relatively straightforward as the components found here are typically held together with push-style clips.
What does a faulty Body Control Module do?
A faulty BCM can cause major problems with a vehicle’s performance and efficiency. If it malfunctions, it can result in random malfunctions of different systems because they are not being properly regulated by the BCM anymore. This can be very dangerous in some cases as certain accidents have been blamed on faulty body control modules that could not regulate essential safety features properly. To prevent such scenarios from occurring, regular maintenance checks should be done so that any potential errors are caught early and rectified immediately before they become major problems in the future.
What Causes a Bad Body Control Module to Malfunction?
The body control module (BCM) is responsible for controlling a variety of functions in your vehicle, such as electric windows and door locks, alarm systems, and even some diagnostic functions. As such, when the BCM malfunctions it can cause a range of problems for you and your car.
Common causes of BCM malfunction include:
Hard impact collisions

Collisions with hard impact can cause physical damage to the BCM and its wiring. This can lead to a variety of issues, such as intermittent electrical problems, failure of certain functions (door locks, alarm systems, etc.), or even complete loss of power in some parts of the vehicle.
Faulty sensors
Faulty sensors are common causes of BCM malfunction. This could be due to short circuits, worn-out wiring, or incorrect installation. In such cases, the BCM may start providing inaccurate information or stop responding completely.
Excessive heat from the engine

Excessive heat from the engine can cause damage to the BCM and its wiring, leading to various issues such as intermittent electrical problems or complete loss of power in certain parts of the vehicle.
Poor connection of the BCM to other electrical components
In order for the BCM to operate properly, it must have a solid connection with other electrical systems in your car, such as the onboard computer and security system. If these connections become loose or disconnected over time, then the BCM will not be able to control the necessary functions.
Physical damage to the BCM itself

If your vehicle is exposed to certain environmental conditions, such as extreme heat or cold, this can cause physical damage to the BCM and result in it not functioning correctly. Additionally, if you’re involved in an accident that causes physical damage to the BCM, it may stop functioning properly as well.
Electrical surges
When there is an unexpected surge of electricity within your vehicle’s electrical system, this can cause damage to the BCM and result in various malfunctions. This type of electrical surge can be caused by things like lightning strikes or power outages.
Faulty relays and switches

If your switches and/or relays within the vehicle are malfunctioning, this can cause problems with the BCM. Faulty relays or switches are usually caused by general wear and tear, as components degrade over time.
Malfunctioning fuses
If a fuse connected to the BCM is worn out or blown, this can cause the BCM to malfunction. This is usually caused by wiring or electrical problems within your vehicle, so it’s important to have a professional take a look at the entire system if you’re having issues with your BCM.
Water or moisture damage
If there is a leak in your vehicle that allows water or moisture to get into the BCM, this can cause it to malfunction. This could be caused by condensation from air conditioning units, large amounts of rain, or even just general wear and tear on seals and components.
Improper programming of the BCM

If the programming of the BCM is not done correctly, it can lead to faulty operation and eventual malfunction. This is usually a technical issue that needs to be addressed by a trained professional.
Corrosion or dirt accumulation
If your vehicle is exposed to harsh environmental conditions and especially if it’s kept outside, dirt, dust, and other particles can accumulate within the BCM, leading to corrosion and eventual malfunction.
By understanding the common causes of BCM malfunction, you can take steps to prevent them from happening and keep your vehicle in tip-top shape for years to come.
Symptoms of a Faulty Body Control Module?
When a vehicle’s body control module begins to malfunction, it is important to recognize the symptoms as quickly as possible in order to prevent further damage. A faulty body control module can cause a number of issues with a vehicle, ranging from minor inconveniences to major safety concerns. Common signs of an issue with the BCM may include:
Repeated Battery Drain

When a Body Control Module (BCM) fails, it can cause a serious problem known as a parasitic draw or repeated battery drainage. Basically, the BCM will keep sending power to an accessory even when it should be turned off – this can lead to a dramatic drain on the battery’s charge, potentially causing it to be depleted in only a few hours. The excessive parasitic draw should be avoided at all costs, as it can have serious consequences for a vehicle’s electrical systems.
Erratic Electrical Function

A malfunctioning body control module can lead to a host of issues with a vehicle’s electrical system, including irregular operation of features like the horn, lights, and windshield wipers. Additionally, sudden swerving of instrument cluster gauges is another symptom that could indicate body control module failure. More often than not, when multiple symptoms are experienced simultaneously, it is likely that the body control module is at fault.
Security System Problems

Vehicles are equipped with a body control module (BCM) that helps facilitate the security system of the car. When this BCM is either failing or faulty, it can lead to intermittent problems with the security system, including issues associated with the keyless and passive entry functions of the vehicle. In other words, if you’re having difficulty using these functions, it could be a sign of a failing or faulty BCM.
Dash Warning Lights
Dash warning lights are an important indicator of a vehicle’s well-being, alerting the driver to any potential issues and providing information regarding the health of their car. When certain control modules stop communicating with each other, they can have an effect on the instrument cluster and cause numerous lights to illuminate all at once, similar in appearance to that of a Christmas tree.

This often occurs when a body control module (BCM) fails to communicate with other important control modules, such as the transmission control module, powertrain control module, or airbag control module. It is essential for motorists to stay aware of dash warning lights and take note of any potential abnormalities in order to maintain the safe operation of their vehicles.
Failure To Start

A vehicle’s body control module (BCM) is a key component of its electrical system, and it can cause a variety of issues if it is not functioning properly. One of the most significant problems that can arise from a faulty BCM is an inability to start the car. This situation may occur due to a failure in the communication between the BCM and the transponder chip, or a failure of the BCM to send the “start” signal when the ignition is switched on. Additionally, if there is a lack of communication between the BCM and other control modules in the vehicle, it can also lead to starting problems.
In conclusion, a faulty body control module can cause a number of issues with a vehicle, from minor inconveniences to major safety concerns. It is essential for motorists to be aware of the warning signs and take swift action in order to prevent further damage. If you think you are experiencing any of these symptoms, it is recommended that you contact a certified technician as soon as possible.
Can You Drive With a Bad BCM?
It is not recommended to drive a vehicle with an issue in its body control module, or BCM. This is because it cannot be predicted how the computer module will act upon being faulty, thus making it impossible to determine the safety of the driver and passengers in the car. Furthermore, even if there were no problems in the past, it is still unable to guarantee that all of the vehicle’s functions such as lights, radio, and other electronics will work properly.
Due to this uncertainty, it may be more beneficial for drivers to get their cars checked at a local mechanic rather than risk having any issues develop spontaneously while driving. In addition to this, some malfunctions can result in major issues such as engine failure which can not only put drivers in danger but also increase repair costs greatly.
Even if some individuals attempt to drive with a bad BCM, they should ensure that their driving environment is safe and take extra caution when on the road. Make sure that all warning lights are working properly, and keep an eye out for any possible malfunctions including erratic electrical functions or sudden changes in speed or acceleration. Additionally, any stalling or non-starting could be signs of a faulty battery control module so these should be looked into immediately.
Can a BCM Be Reset?
Can a Body Control Module (BCM) be reset in order to restore full function? The answer is yes, but only if the internal circuitry is in proper working order. A reset might be necessary if the module has encountered a “glitch”; however, the procedure for each make and model of vehicle can vary greatly.
For instance, Ford, Dodge, and Chevy/GMC all have different procedures for resetting a BCM. In most cases, this involves disconnecting the vehicle’s battery from its power supply for a specified amount of time.

However, other vehicles might require removing a specialized fuse instead. Therefore, it’s important to consult factory-specific service literature for your specific vehicle before attempting to reset its BCM. Doing so can help you avoid any permanent damage that could occur otherwise.
It’s also important to remember that BCMs are responsible for multiple tasks within a vehicle such as relaying information between various systems like the engine or lighting system. That’s why it’s essential to properly reset your BCM if experiencing any kind of issue with it; otherwise, you could be putting yourself at risk while driving.
The process of resetting a BCM can be tricky since every make and model varies; therefore, it’s good practice to consult professional auto technicians who specialize in this area before attempting a DIY job you’re unfamiliar with.
Bad Body Control Module Repair & Replacement Cost
There are three common ways to repair a bad Body Control Module (BCM). These vary in terms of cost and complexity.
- BCM reset
- Reprogramming BCM
- BCM replacement plus reprogramming
1: Control Module Reset
A reset of the BCM may be all that is needed to fix an issue with the system. However, it is important to follow manufacturer-provided instructions as an incorrect procedure could cause further damage. A mechanic can perform a reset of the BCM by disconnecting the car battery or removing a certain fuse for a specific length of time; this should only incur a diagnosis fee which is typically under $100.
2: BCM Reprogramming
If resetting does not solve the problem, then reprogramming may be necessary. An automotive electrician will connect to your car and check for errors which must then be fixed. This requires specialist labor which usually costs between $300 – $600 depending on how severe the issue is.

3: BCM Replacement and Reprogramming
If physical damage has occurred to the BCM, replacement of the unit with a new one may be necessary. Such damage can likely occur due to being in an accident, water intrusion, dust/dirt, overheating, bad solder joints, components damaged during production, or criminal tampering amongst other possible causes. The average cost for buying a new BCM unit is around $400 plus another $200-$300 for labor including installation and software downloads; meaning you should expect to pay approximately $600-$1,200 in total for this solution.
In conclusion, the cost of repairing or replacing a bad BCM depends on the cause and severity of the issue. If you’re dealing with an unresponsive system, then it’s likely only going to be a diagnosis fee which is relatively inexpensive; however, if physical damage has occurred then replacement plus reprogramming could add up to around $1,200.
Therefore, it’s important to seek professional help in order to accurately assess and diagnose the issue, before deciding on a course of action. When attempting any repairs or replacements, always ensure that you follow manufacturer-provided instructions and safety precautions. This will ensure the longevity of your BCM and vehicle as a whole.
What is the Bad Body Control Module Repair Process?
Knowing how much you will be spending on a body control module repair begins with understanding the entirety of the process. When the body control module (BCM)t malfunctions, it is necessary to diagnose the problem and then look for an appropriate repair. Here is how the mechanic will go through the process:
Diagnosis of the BCM

The first step in repairing a body control module is to diagnose exactly what the problem is. This is done by connecting an OBD2 scanner to the vehicle’s computer and reading any error codes that are generated. The mechanics will then determine what parts need to be replaced or repaired.
Remove the Connections to the BCM
The repair process for a bad BCM starts with disconnecting the battery for safety precautions. After this initial step, the mechanic needs to locate the BCM unit, which typically resides either behind the glove box or the center console. To provide access to this part of the vehicle, any bolts or connections that secure the pieces must be removed.
Discard old the BCM
Once all components have been detached from their surrounding areas, it’s time to remove and discard the old BCM unit. This involves unscrewing any screws that keep it in place along with releasing its connector clip from its electrical connection.
Install a New Module

Then comes what could be considered a crucial stage: installing the new module in its place and programming it to match your specific car’s parameters. This process is completed in reverse order and programmed to best fit your vehicle’s individual needs. By relying on the expertise of an experienced professional, you can rest assured that everything will be handled with precision and care.
Test the New BCM
Finally comes testing if everything is functioning correctly. This entails connecting back the battery and inspecting whether each element is running at full capacity before concluding that this whole process has been successful. The full duration of repairing a BCM may take up to 90 minutes and will impact how much you end up paying for this service overall.
Given how essential this component is for both your vehicle’s performance as well as your own safety while driving, neglecting potential problems associated with a malfunctioning BCM should never be an option; instead, seek out professional help so they can assist you with diagnosing and replacing any faulty parts if needed – ensuring that your vehicle remains in perfect condition throughout its lifetime!
How to prevent Body Control Module from going bad?
There are a few steps you can take to prevent the Body Control Module (BCM) from going bad.
Check for proper installation
Make sure that all connections between the BCM and other components, such as the sensors, relays, and switches, are securely attached and properly grounded. This includes ensuring that any exposed wires are sealed with electrical tape or shrink-wrap to prevent moisture from entering the connections.
Check for clean connections
Inspect all connection points for dirt and corrosion, as these can have an adverse effect on the BCM’s functioning. Make sure that any exposed components such as terminals and connectors are free of dirt and debris before re-sealing them with electrical tape or shrink-wrap.

Avoid heat damage
The BCM is heat sensitive and can be damaged if exposed to extreme temperatures. Make sure the BCM is mounted in a location that won’t be exposed to direct sunlight or other sources of intense heat. Install a thermal shield, if necessary, to protect the module from excessive heat.
Check for software updates
The BCM’s programming is crucial to its functioning, so make sure it has the latest software version installed. This can be done by connecting the module to a laptop or other device and downloading the updates from the manufacturer’s website.
Check for power surges
Make sure that all electrical components connected to the BCM are operating properly and not causing a surge in current. In addition, install a voltage regulator or surge protector to prevent power spikes from damaging the BCM.
Use a code reader

Using an OBD-II scanner to read codes from the BCM can help you identify and address any issues with the module before it fails completely. Regularly checking for diagnostic trouble codes (DTCs) using a code reader can help keep the BCM in good working order.
Replace aging components
If any of the components connected to the BCM are aging, replace them before they cause further damage. This includes any sensors, relays, and switches that may be malfunctioning due to old age or wear and tear.
By following these steps, you can help ensure the longevity and proper functioning of your BCM. Regular maintenance and inspection of the module can help prevent it from going bad and save you money in the long run.
Wrapping Up
In conclusion, it’s important to be aware of the issues that can arise from bad body control modules. Not only can these issues cause problems with the performance of your vehicle, but they can also be expensive to repair or replace as well. Therefore, it should be addressed as soon as possible. The most common causes are corrosion in the electrical connectors, water damage, faulty wiring, and failing components. Symptoms you might experience include malfunctioning electronics and warning lights on your dashboard.
Depending on the type of car and module you have, repair/replacement costs can range from just $100 to $1,200. If you’re ever faced with this issue, it’s always best to consult an experienced auto technician who can inspect the module and provide you with accurate estimates for any necessary repairs or replacements. Taking care of these types of issues quickly is essential in avoiding further damage to your car’s electrical system or other related components that could prove more costly in the long run.
NOTE: Please note that this article is meant for informational purposes only and should not be taken as professional advice. If you are experiencing any of the symptoms listed above, it is highly recommended that you seek out the help of a certified technician in order to diagnose and resolve your issues.