Brake and Battery Light On? Here’s What You Should Do

Brake and battery light on indicate a problem with the car’s charging system. This could mean that your alternator is faulty or totally damaged.

Below are some of the major culprits of this issue:

1. Faulty Alternator

The device that turns mechanical energy into electrical energy is called an alternator. It’s a very important part of the electrical system in your car, and if it’s not working right, it can cause several problems.

When you start your car and turn on the headlights, for example, the alternator sends electricity to charge up your battery so it has enough power to run all of these other things. Nothing would work without an alternator or battery. If it is damaged, your brake light and the battery light will come on.

Fixing a Faulty Alternator

If you’re having trouble with your alternator, then you may want to take a look at the steps below:

  • The first thing that you need to do is check the battery. If you have a bad battery, then this could be causing your alternator issues. Make sure that it’s fully charged and that it has been replaced if needed.
  • Next, check for loose connections on the battery terminals or wires. If these are loose, then they could be preventing the alternator from charging properly.

If these steps don’t fix the problem, then it might be time to replace your alternator entirely.

2. Malfunctioning Voltage Regulator

The voltage regulator is a device that regulates the voltage of the battery. It is usually located on the alternator. If it malfunctions, your car may not start, or it may not be able to keep up with all of the electrical demands placed on it. A voltage regulator that is failing can cause erratic behavior in other electrical components such as lights and radio receivers.

Fixing a Malfunctioning Voltage Regulator in a Car

  • Make sure the car is off and the engine is cold.
  • Use a voltmeter to check for power at the battery terminals, as well as between the alternator output terminal and ground. If there is no voltage at all, the alternator may be bad and needs to be replaced.
  • If there is a voltage at both locations but it’s not enough to run the car, then you may have a bad voltage regulator or wiring problem that needs to be addressed by an auto repair professional.

3. Broken or Loose Wiring Connections

Broken or loose wiring connections are some of the most common causes of brake and battery lights coming up. It can be caused by a number of things including corrosion, water damage, and poor contact between the wires and their connectors.

Fixing Broken or Loose Wiring Connections

To fix this problem, you need to check to see if any connections are loose or if any wires are broken. If the wires in your car are broken, you’ll need to get new ones.

If the problem is caused by corrosion or water damage, you should use a brush cleaner to clean those areas well and then seal them with a heat-resistant sealant so it doesn’t happen again.

If you find that your car’s battery cables are broken or corroded, you should replace them right away. This could cause an electrical short circuit, which could damage your car’s electrical system in a big way.

4. Failing Braking System

If your brake and battery light is on, it’s likely a sign that one or more components in your braking system need to be replaced. The most common culprits are worn-out pads and rotors due to excessive use over time. In some vehicles, this may trigger a service brake assist warning on the dashboard.

Another common issue is low fluid levels or contamination inside the brake lines, which can lead to an unsafe braking experience and cause an increase in maintenance costs over time.

Fixing a Failing Braking System

  • Check your brakes. Make sure they’re not worn out or leaking fluid. If they are, make sure to replace them immediately.
  • Check your brake pads and rotors for wear and tear or corrosion. If there is any of either of these things happening, now would be the time to replace them.
  • Check your calipers for leaks or corrosion; if there are any of either of those things happening as well, now would also be an excellent time to replace them.

5. Low Brake Fluid

If your battery and brake warning lights are on, it might be because your brake fluid is low. This can happen if you let your car sit for too long without driving it.

When you don’t drive your car, the level of brake fluid in the master cylinder will drop, which means that when you do drive your car again, there isn’t enough brake fluid to keep things working as they should.

Fixing Low Brake Fluid

Find out if there’s an issue with your brake fluid by checking the level in the reservoir when the engine is cold. If it’s less than 1/3 full, add some brake fluid until it reaches the top of the reservoir.

6. Defective Sensors

Your battery and brake light can come on because of a faulty sensor. Sensors are crucial parts of your car. They help to keep you and your passengers safe, and they also make sure that your engine runs efficiently.

When a sensor is not working correctly, it can cause the lights to flash on the dashboard. This means that there is an issue with your vehicle’s mechanics, which could lead to serious problems down the line if left unchecked.

Fixing Defective Sensors

First, check the sensor for any cracks or holes. If you find any, you’ll need to replace them. If there’s no damage, you’ll need to clean the sensor with a soft cloth and warm water. You can use a little soap if needed, but make sure it’s completely dry before putting it back in your car.

If your sensor still isn’t working properly after cleaning it, try replacing it with another one from your car’s parts bin. Make sure to get an exact match so that your engine runs smoothly again.


What Do I Do When My Battery And Brake Light Come On While Driving?

First, if your brake and battery warning lights illuminate while driving, pull over to a safe location and inspect your vehicle. Check for potential leaks or burnt odor.

Also check for loose or corroded cables, damaged battery terminals, and other issues that may be causing the light to turn on. If you find any problems with the vehicle’s system, get it fixed as soon as possible by a certified technician at an auto repair shop.

In addition to those, check underneath your hood for potential leaks or a burnt odor coming from the wiring. If something looks out of place or broken, double-check that you’re able to turn off any potential problems before attempting to drive away again.

It may also be worth looking at other areas such as your engine or alternator if these components are suspected of causing issues with your electrical system.

Is It Safe to Drive with the Battery and Brake Lights On?

It is very risky to operate a vehicle with the brake and battery warning lights on. They suggest that your automobile will soon stop running, which constitutes an emergency given that you are unable to go a significant distance in it. It is highly recommended that you switch off all of the electrical components of your car that are not essential to its operation.

These include music, power windows, automatic lighting in the cabin, and an air conditioner. You will be able to travel further before the battery is completely depleted if you do it this way.

Nevertheless, you should never switch off the headlights if you are driving at night or in poor weather conditions.

To avoid being left stranded on the highway in the event that your car suddenly stops working while you are going a long distance, it is in your best interest to have a tow truck’s number readily available.

In addition, before driving to a mechanic’s shop, you may pull over to the side of the road, carry out a visual inspection, and determine whether or not you can do a few repairs yourself. In the next part, you’ll find several easy solutions that can help you go back home.


The brake and battery light is an indicator light that shows up on the dashboard of your car. It’s there to keep you safe while driving, but if both lights come on at the same time, then it means there’s something wrong with your car. Fixing the problem as soon as possible is very important.

Also, your car’s brake and battery lights may come on at the same time for the following reasons: a broken alternator, low brake fluid, broken sensors, a failing braking system, a broken voltage regulator, or broken or loose wiring connections. By doing the steps above, you can fix all of these.