Blog Car Care Advice Why Do Brake Lights Stay On When the Car Is Off & How to Fix?
Car Care Advice

Why Do Brake Lights Stay On When the Car Is Off & How to Fix?

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Wondering why your brake lights stay on when your car is off?

Malfunctioning brake lights may be due to a faulty brake light switch or pedal spring. And while it may seem like a small issue, it can seriously affect road safety.

But don’t worry!
We’ll delve into what causes the brake light issue and whether you should risk driving with it.

This Article Contains:

Let’s get started.

4 Reasons Your Brake Lights Stay On When Your Car Is Off 

Here are common causes of malfunctioning brake lights:

1. Faulty Brake Light Switch or Stopper

When you press down on the brake pedal, it closes the stop light switch (also called the brake light sensor, brake switch, or brake pedal switch) to activate the rear brake light. 

However, if the brake pedal switch is bad, it may not know when the brakes have been released. If that happens, your brake light may stay on even when the ignition is off.

Similarly, the brake light switch stopper or striker turns off the switch when the brake pedal arm is released. If the stopper or striker is broken or missing, the sensor will think the brake pedal is depressed — keeping your brake lights on. If it’s missing, check for a rubber or plastic piece on your car floor.

2. Defective Brake Pedal or Spring

If the brake pedal arm doesn’t return to its position after you’ve released the brake, you may have a defective brake pedal or pedal spring.

This can happen due to: 

In both cases, the brake light will stay on since the brakes remain depressed. You may also face additional brake pad and rotor issues since the brakes are constantly engaged. 

3. Malfunctioning Electrical System

Faulty wiring or other electrical system issues, like a blown fuse or damaged wiring harness, can also affect your brake light circuit, causing the light to stay on or work intermittently.

Any damage to this brake circuit could also impact your tail lights.  

4. Wrong Light Bulbs Installed

Although uncommon, you could have installed the wrong brake light bulbs. 

Your car has a brake socket that’s meant for either a one-circuit (same circuit for both brake lights) or a two-circuit light bulb (separate circuit for each brake light). If you install the wrong bulb in the brake socket, it can short the brake light circuit and lead to the lights staying on.

Remember: Brake lights may share the same bulb as the tail lights in some vehicles. In others, you may have separate brake and tail light bulbs. So, you should get rear light bulbs based on your vehicle’s setup. 

Now, you may wonder if brake lights staying on is a serious problem.
Let’s find out. 

Is it Safe to Drive with Malfunctioning Brake Lights?

No, you shouldn’t drive with malfunctioning brake lights, especially if you’re unsure what’s triggering it.

Brake lights are one of the most important elements of road safety. If they’re constantly on, drivers behind you won’t know when you’re braking, which could lead to accidents.

And that’s not all!
Here’s what else could go wrong:

Let’s see what you can do to resolve it.

How to Fix a Faulty Brake Light

Sure, fixing a brake light is an urgent repair. But if it isn’t done right, you could risk an accident since your brakes and brake lights may not work properly. So, it’s best to let an experienced mechanic handle the job. 

Here’s how a mechanic will address the issue: 

  1. Disengage the battery by disconnecting the negative cable
  1. Check if the brake pedal works properly and returns to its original position when released. 
  1. If the pedal is okay, check for a bad switch by pressing down on the brake pedal. A bad switch won’t trigger the brake lights or the 3rd brake light (a high-mount stop light). They’ll replace the old switch with a new switch.
  1. Inspect whether the rubber or plastic stopper is broken or missing. They’ll replace it with another stopper of a similar width if needed. 
  1. Disconnect the wiring harness from the stop light switch and look for damaged connections. They may use a test light to check the circuit’s current flow.
  1. Look for other brake system issues and address them.
  1. They’ll access the fuse box based on your manual’s wiring diagram to inspect the brake light fuse for signs of burning or damage. They’ll replace the fuse or the entire fuse box if you have a blown fuse or there are signs of corrosion.

Note: A new switch must be installed in an unlocked state, with its plunger extended out.

Have more questions about the brake light?
Let’s answer them!

3 FAQs about Brake Lights

Here are answers to common queries about brake lights:

1. How Do Brake Lights Work?

The brake lights work independently from other light systems, like the headlight, daytime running light, and tail light. It’s based on the brake system, which contains various components, including: 

When you use the brake pedal, the plastic or rubber stopper on the brake pedal arm makes contact with the light switch and closes the brake circuit, activating the rear brake light. When the brake pedal is released, the stopper moves away from the light switch and opens the circuit — turning the lights off.

If there’s an issue with any of these components, the rear light assembly (including the tail light and 3rd brake light) may not turn on or off.

But what about the parking brake?
Since you release the brake pedal after applying the parking brake, the brake rear light isn’t activated. However, you will see a dashboard warning light whenever the parking brake is on.

2. How Much Does it Cost to Fix a Malfunctioning Brake Light? 

A brake light fix can cost between $40 to $400, depending on the labor charge, the replacement parts, and your vehicle’s make and model. 

Here are estimates for some repairs and replacements with labor costs:

However, if you have a complex electrical fault, you may have to consult a specialist auto electrician to resolve the issue. This could cost anywhere between $100 to $1000. 

3. How Long Do Brake Light Bulbs Last?

Whether on a Honda Motor Company, Toyota Motor Corporation, or any other brand’s car, brake light bulbs typically last up to four years before their filaments break. 

However, the period could be more or less depending on the type of bulbs (LED, halogen) installed and your driving habits. 

Brake Confidently with AutoNation Mobile Service

Brake lights that don’t go off can affect you and the people driving behind you on the road. That’s why it’s best to resolve a brake light issue as soon as possible — before it jeopardizes your safety. 

Need urgent brake repairs?
AutoNation Mobile Service will tend to your auto repair and maintenance needs right in your driveway.

Contact us to have our experts fix your brake lights or other automotive issues.