Summary: Does your brake lights stay on permanently while driving? This article shows you how to diagnose and fix the challenge yourself, in DIY fashion.
The twin rear brake light system on an automobile is a very important safety feature.
So important is it that in 1985, the US government mandated all vehicles built from the following year to carry a third, higher-mounted brake light, besides the customary rear two.
The thinking was that this third, higher-mounted brake light would attract the attention of other motorists better than the lower two, because of its vantage position.
Not done, all the states in the US (to my knowledge), penalize driving without functional brake lights.
This alone should tell you something: brake lights are no joke and the business of notifying folks who are driving behind you of your intention of slowing down is sacred and non-negotiable.
Aware of all these, what do you do when after a drive, you park your vehicle on the driveway and as you make progress to your apartment/room, you notice that all three rear brake lights have refused to go off and as a matter of fact, are shinning as brightly as if your foot is still firmly depressed on the foot brake?
The first thought will be that, someone, somehow, is in the vehicle and maybe, wants to move it away, once you clear off; he/she is warming up to driving away.
As you curiously and cautiously check, no one is left in the vehicle and the driver’s seat is very vacant, even from a few feet away.
The second thought flows in (after you heave a sigh of relief): there’s something physically depressing the foot brake pedal that you must have missed while driving.
Gingered up and renewed with hope, you proceed to open the vehicle and inspect it.
Nothing.
You check back to see if the brake lights are still on…of course, they are…and they are now shining brighter than the moon, with the fast approaching dusk.
You whip out the shiny OBD II scanner you recently ordered from Amazon and plug it into the OBD II port…for the first time, you’re disappointed with otherwise positive feedback: this vehicle has no fault codes.
You check pending codes; same story.
Officially, an otherwise great day has begun scheming on how to be bad already….
What Causes Your Brake Lights to Stay On?
There are some pretty nasty – and not-so-nasty reasons why your brake lights won’t go off, even with your foot off the brake pedal and the ignition switched to the ‘off’ position.
Here are the likely causes, starting with the MOST LIKELY.
1. Bad Brake Switch/a Brake Switch Not Properly Mounted or Adjusted
The brake switch on most vehicle models is mounted along the brake pedal – in such a manner that when the brake is depressed, the switch is activated and when the brakes are released, the switch, conversely, is deactivated.
Essentially, what this makes certain of, is that the brake lights come on when the brake pedal is depressed and the lights extinguish, once the pressure on the brake pedal is released.
As explained simply above, this created the ‘on-off’ effect you see when a vehicle with brake lights is being used.
2. Wrong, Bad, or Compromised Bulbs Used
The use of the wrong bulb types on the brake lights can go a long way to causing challenges like having the lights mess around or fail to go off when they should.
The same thing applies to compromised bulbs or bulbs that have gone bad and need to be replaced.
When faced with a situation where your brake lights stay on, checking on the actual bulbs to make certain that they’re in great working condition should be one of the items you need to check before bothering with other more complex checks or fixes.
Personally, I’ve been privileged to resolve many brake (and headlight) related matters by simply changing the bulbs to the recommended spec and making sure that the replacements are new and functional.
3. Naked Wiring
Compromised wiring to the rear brake lights can also cause a lot of challenges for the brake lights themselves to warrant them staying brightly on when they have no business remaining illuminated.
Usually, such a compromise happens when the covering of the wires is compromised and the naked wires touch themselves (or any other metal part of the vehicle).
The first sign of such a challenge is usually the flickering of the brake and rear lights generally, when both in use or not.
This doesn’t happen all the time, however: sometimes, the brake lights (and other lights) come on and simply refuse to go, no matter what you do.
In such an instance, it makes sense to check up on the wiring, especially if any of it happens to be externally exposed.
If you find such wires exposed – PVC tape will do a great job of masking the exposed parts and the issue will be sorted, as simply as that.
4. How About A Blown Fuse?
If you’ve done all the suggested above and the brake lights still stay and remain on, it would be a smart decision to check on the fuse box for a blown fuse.
Usually, on most models, there are two fuse boxes: one by the driver’s side foot well and another in the engine bay.
With the help of your owner’s manual, locate the correct fuse box and check for the fuse controlling the rear/brake lights.
Once you find it, make sure that it is changed to a similarly rated fuse and replaced snugly, without any clearance.
What You Should Do If Your Brake Lights Do Not Turn Off
More than 90% of the time, in my experience, when the brake lights stay on, the challenge is usually with a bad brake switch or a brake switch that isn’t properly adjusted.
Manually depressing the tip of the brake switch while still attached to the brake pedal is a great way of checking out if it is still in good working condition.
If it is, what needs to be done is a simple adjustment to make certain that the brake lights go off, coming on only when depressed and needed.
However, if depressing and releasing the ends of the brake switch doesn’t cause the brake lights to power on and off, it has certainly failed – and requires a replacement.
In that case, all you need to do is to order a replacement, unscrew the old one, and torque on the new one, and the problem is solved!
If you’re interested in watching the video process of the procedure or generally, prefer visuals, the video I shot sometime back and shared below remains instructive.
Wrap-Up: Is It Okay To Drive With Brake Lights On?
Without mincing words or beating about the bush, NO – you should get your brake lights fixed as soon as possible when they refuse to go off.
The reason is simple: other vehicle owners rely on the brake lights of your car to make critical driving decisions such as braking, overtaking, and increasing speed.
With the brake lights permanently on, this all-important safety measure is negated, with the drivers behind you left without a clue when you depress the brakes and accidents are likely to result as a consequence, especially rear endings.
Luckily, this is a very DIY-friendly replacement and takes only a few minutes to an hour, max – depending on the year and model of your vehicle (as the article above has shown).