Jeep Brake Lights Not Working When Headlights Are On

The brake and tail lights are vital safety features in your Jeep. They signal to the other drivers in a row whether your Jeep is stopped or moving on. Therefore, having a functional brake light is essential, especially when driving on an icy path or in heavy rain.

So, this blog will walk you through all the possible reasons why Jeep brake lights don’t work when headlights are on. 

Therefore, keep scrolling and find out if you are going through the same issue.

Why doesn’t the brake light work when the headlights are on? (Reasons with solutions)

This blog will discuss all the potential reasons why Jeeps have a troublesome brake light when the headlights are pressed.

1: Faulty electrical ground circuit

A bad ground circuit is the most common issue when the brake lights do not work while headlights are turned on. 

Jeep consists of numerous ground connections at different places. If any of the ground connections go bad, the current cannot find a return way to the ground and reverts itself to any other pathway, which results in a diminishing brake light.

Solution

Locating the faulty ground connection could be a tiring job. In this case, you can take the help of the wiring diagram of your vehicle to help you locate that single bad connection. 

You can also seek help from a professional mechanic to locate and fix the bad ground connection.

2: Corroded terminals

Corroded terminals to the Electronic Control Module (ECM) can be another potential reason for brake light disorder. Sometimes during the previous repairing session, terminals are not tightened properly or Scoth-Lock connectors have been used that result in continuous paving of moisture ultimately leading to corroded terminal problems.

Solution

Replacing a corroded wire or terminal is not a tedious job, and you can quickly fix it without the help of a mechanic. You just need to have some basic electrical knowledge.

3: Bad headlight switch

The headlight switch is responsible for the functionality of headlights, parking lights, and tail lights. If the button has some issue, all the lights connected to the switch will be affected due to the incomplete flow of current in the circuit.

Solution

Replacing the headlight switch is the only solution to this problem.

4: Fused/ill-fitting bulbs

Fused bulbs can also be a reason for not lighting. Moreover, using the wrong bulbs or if the brake lights are poorly fitted may also lead to a fault in lightning.

Solution

If the bulbs are fused, replace them, but if they are not properly fitted, then take out the whole assembly and check the connections and threads. Make sure you tighten the lights properly. If both hacks don’t work, check whether you have used the correct type of bulb.

5: Faulty series circuit

Many times, some of the model Jeeps have their light joined in a series circuit, and if any of the bulbs at the start or end of the circuit fuses, it also halts the working of other bulbs. 

Solution

In this case, you must inspect the whole circuit and work through each light and terminal. Even if you have to check the grounding nodes and the power circuit, if any of the issue lies there, you can quickly repair it if you are an electrically inclined. Otherwise, seek help from a mechanic.

6: Weak battery

Low voltage battery can also be a culprit if your headlight, tail light or any other light assembly is not working. You can easily check it by connecting a multimeter through the terminals of your battery and if it shows anywhere below 12.6V then you have successfully troubleshooted the root cause.

Solution

If you have concluded that the brake lights are not working due to the weak battery, then recharge it on the first go. But ultimately, you must change the battery if it continues creating trouble with other electric circuits. 

Final thoughts

This blog gives you a complete insight into why the brake lights don’t work when the headlights are on. Also, we have provided you with a complete solution for investigating and fixing the problem on a DIY basis. Still, if you cannot follow the leads, you can seek the help of a professional mechanic anytime.

But make sure that all the lights of your Jeep, including brake lights, parking lights, and tail lights, are functioning correctly, conversely, you are endangering the lives of others.

Till next time, happy jeeping!

FAQs

1: What is the difference between a brake light and a tail light?

Tail lights work in conjunction with the headlights. It means whenever you turn on the headlights, tail lights illuminate on their own. While brake lights only light up when you depress the brake pedal. There is a color difference in both the lights as tail lights are red and brake lights are bright red.

2: Are tail lights and brake lights the same?

No, tail lights and brake lights are different as tail lights remain lightened as you switch on the ignition and turn on the headlights, while brake lights only illuminate when you apply pressure on the brake pedal.