Body Control Module Reset: Instruction From Technicians (Plus 5 Tell-Tale Signs You Need One)

The automotive industry has been involved a lot in recent decades. As a result, newer car models are truly a feast for electronic systems. Unlike their predecessors, which were mechanical, vehicles today are stuffed to the gills with actuators, control modules, and sensors. 

Yes, it brings countless benefits, such as safety features, advanced performance, and improved reliability. However, modern technology also means modern problems requiring modern solutions. Body control module reset is one of them.

Body Control Module: What Is It Exactly? 

Did I just mention how modern technology affects the automotive industry? The body control module is proof of this! Also known as the BCM, this tiny but mighty part is the central processing unit of an automobile. Since many electronic features like headlights, door locks, and windshield wipers are linked and managed by the BCM, the car can operate them with ease. It’s as important as the CPU in your computer, to say the least. 

This might remind you of the Engine Control Module (ECM), which also controls various electronic auto functions. However, the ECM is responsible for engine-operated function, while the BCM runs the systems external to the engine. So if you are having problems with coolant or can’t start the car, the BCM is not a prime suspect. 

But that doesn’t make it less critical: The role of a body control module becomes bigger and bigger as recent car modern utilize electrical systems more and more. As important as it is, though, the BCM is often susceptible to corrosion, heat, and moisture and also vulnerable to humidity. Indeed, this powerful part can fail you sometimes!

Warning Signs Of A Malfunctioning Body Control Module 

How do you know when a BCM runs faulty, then? Well, the symptoms become evident from the systems it manages. Drive Revolve will go through some common signs: 

Warning Lights On The Dashboard

When the BCM fails to communicate with other systems (like the power train control module, the airbag control module, or the anti-lock brake module, for instance), it won’t be able to determine whether they are functioning correctly. 

Therefore, the BCM will trigger flashing warning lights on the dashboard as it senses issues with the various modules it can no longer reach out to. 

When this happens, pinpointing the specific problem is quite simple, given that your car doesn’t suffer from multi-system failure at once. The one at fault here is either the BCM or the controller area network (also known as CAN.)

The Battery Keeps Draining 

When the body control unit has a short circuit or malfunctioning circuit board, you will quickly notice the battery is depleted. Parasitic drains, which occur when the systems run by the BCM draw too much power, are one possible source of this problem.

As mentioned, the BCM manages many electrical systems, from the headlights to the parking sensors. If it fails to perform the functions, electrical parts may remain on when they should be switched off. That’s why the car drains the battery even after being parked overnight. 

That’s a nightmare while you’re on the go with a dead battery. But applying some dead battery tricks can be the life savior or you must find ways to get the nearest repair center.

The most obvious example is interior lights remaining on after the door was locked or the radio staying active when the ignition is off.

Electrical Systems Malfunction 

A BCM’s key role is to control the electrical modules in a car. Thus, when there is a problem with it, one of the symptoms is a decline in efficiency of these electrical modules. 

Thus, if you see the dials, lights, locks, horns, warning chimes, stereo, clocks, etc., malfunctioning or operating incorrectly, your BCM may suffer. At this time, you will need to perform a body control module reset. 

The problem only sometimes results in a complete electrical system failure. At the early stage, the symptoms are insignificant and mostly harmless. They will worsen with time, though, so don’t ignore if the odometer gets reset whenever you start the car!

Jerking Under Acceleration

When a car accelerates, you can feel some vibrations inside the cabin. That’s perfectly normal, but if you start to feel excessive shaking and humming noise, something has gone wrong here. Troubles with the BCM might be the culprit. 

The more you slam on the throttle, the more apparent this becomes. Under intense acceleration, the shaking is very noticeable. However, you should be warned: The BCM is not the only possible cause. There can be other reasons for engine shaking, like a clogged filter, a failing catalytic converter, or a problem with fuel injectors. 

Burnt Fuse Box

The fuse box is the next thing to get affected when the body control module goes wrong. A burned smell or smoke coming from the fuse box are two tell-tale signs that the fuse box has overheated and failed. 

Overheating is the result of circus breaker burns. When the BCG goes wrong, the systems will be overloaded, suffering from power surges or arc faults. These will suddenly heat the circus, possibly leading to the fuse box getting burned. 

How To Reset Your Body Control Module?

You now know the signs of a faulty BGM, so what? If you experience one or more symptoms above, a body control module reset might be all that you need to restore the vehicle back to its health. But you have to do it the right way: If the procedure is not performed well enough, you will cause irreversible harm to your baby instead of fixing it. 

Sometimes resetting the BCM is not enough – you’ll have to reprogram it. In that case, only a dealer or specialist can do the job as they possess specialized diagnostic scan tools to perform the reprogramming procedure. Still, if you want to try it at home first, scroll down! Below are five simple steps to repair the BCM and alleviate electrical issues. 

Step 1: Body Control Module Reset – Troubleshoot

As I previously said, some of the warning signs above might be caused by the body control module. However, they might also signal problems with other parts. 

So how do you know if you need a body control module reset? The simplest way is to check the connection between the BCM and the fuse box. Disconnect the battery’s negative terminal and switch the ohmmeter to the OHMs setting. Then, choose one of the leads and connect with a terminal on the BCM connector. The other lead should be connected to the respective terminal of the fuse box. If there is no reading, then you have a faulty BCM. 

How to locate the body control module fuse box 

Step 2: Disconnect The Battery 

After you’ve come to the conclusion that your BCM goes wrong, the second step is… be careful! Remember to disconnect the battery before doing anything else. I often do it with a ratchet or wrench. You wouldn’t want to get an electric shock while doing the operation, right? 

Step 3: Locate The Body Control Module 

Just like most car components, the BCM can be found in various locations depending on each model. Oftentimes, you can spot it beneath the dashboard panel on the right side of your steering wheel. In some autos, it’s necessary to disassemble some of the dashboard’s bits to access the BCM. 

But why waste your time guessing? An auto always comes with a manual, which is helpful in situations like this. Using the handbook, you can locate the control module right away. 

Step 4: Remove It And Reinstall 

Once you’ve removed the surrounding parts, you can remove the body control module. I’d recommend using a ratchet to perform this action, removing the bolts that keep the malfunctioning module in its place. If you notice a connector clip attached to it, you will have to remove it as well to detach the BCM from the rest of the car. 

Now, let’s work on the installation of the new one. Remember to reattach the connector clip into it, then secure it using the bolts you just removed. Put back the center console and the glove box in their positions. 

Step 5: Reconnect The Battery And Test

To wrap up, you will have to connect the battery again. This restores the electrical supply through the BCM and other electrical components. 

After connecting, test and see if the problems that made you reset the BCM have been solved. If yes, you should be proud of yourself for doing a good job. That does it for our DIY project of performing a body control module reset!

What’s more, many technical errors could be done with DIY method, like installing the Halogen headlight bulbs or LED lights. As long as you experience and sufficient tools, have things done on your own!

How to reset a body control module without going to the dealer?

Frequently Asked Questions

“Take Care Of Your Car In The Garage – It Will Take Care Of You On The Road”

The body control module is a complex part of your car. Although it serves great purposes, it is also very sensitive. 

Thankfully, when issues arise, and you need a body control module reset, this fun auto part sends signals (pretty apparent ones, don’t you think?). So, to take good care of your car, pay attention to even the slightest sign. Tackle the problem right away before things get messy. It could take some time but it will help you prevent any trouble on the road!