Car or Truck Brake Lights Not Working? How to Diagnose Tail Lights 

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Start with the bulbs. Then go to the rear connector. Then go to the wiring harness that feeds the rear connector. If you have power at the end of the harness the problem has to be either in the taillight harness or the bulb. This assumes that you have power to the 3rd brake light and your cruise works.

What if your two lower brake lights are out but the third is working?

I have a 05 crown Victoria police interceptor when a brake switch goes on this car it doesn’t come out of park but for some reason my brake lights don’t work but it goes into drive could this still b brake light switch?

On the 96 Tahoe brake lights are on but when you apply the brakes you get no brake lights. Checked fuses and replaced brake light switch and lights are on but when you brake no brake lights

What about tag light also

What do you do if only your brake lights stay on? even if the vehicle is parked and off? The light switch and the front lights are off but both brake lights in the back stay on?

1:15 test light / probe testing fuses on both sides. Key on so all fuses hve power 3:38 test light testing bulb socket. Put on battery-positive to test the ground 4:20 Test light on 3rd brake light socket using the probe and a pick 4:52 if one side works and the other doesnt, then check wires to where they connect together before they get to brake pedal 5:20 IF ALL LIGHTS aren't working, most common cause is brake-light switch. Use Jumper harness...???? 5:30 If the lights work using jumper harness, the Switch is bad.

Really appreciate the knowledge here, yet I'm still without working brake lights on a 2005 Camry after going thru these steps. Bulbs, fuses and grounding wires are good, replaced brake switch as well. Got a Haynes repair manual for a 2001 camry- If I'm interpreting the wiring data sheets correctly, it looks like a " light failure sensor " connects between the brake stop switch and the tail and stoplight bulbs- tail lights are working though . My question is where is this sensor located and could part of it be defective for the brake lights and yet still allow the tail lights to function?

This didn’t help. After 8 videos I’m getting dumber.

Yes, I have a 2003 Tahoe, 4.8 2wd. Brake light trouble began when aftermarket taillights (LEDs) that came with vehicle went out; no turn, brake, or running lights. Changed back to OEM brake light assembly, changed out bulbs and removed the adapter that enabled the LEDs to work with OE light socket. After that turn signals and reverse light (white light) began to work, and the running/marker lamps work; still no brake lights though. Changed all possible fuses in dash block as well as fuse box in under hood. Still no brake lights. Found your video about brake light pedal switch, just changed that out, was difficult because I had an extra bracket in the way. Plugged in switch, retaining clip reinstalled, checked brake lights, still not working.....🤔🤔🤔. I'm at my wits end... Any further advice you can offer. Btw: the pedal is now very firm, vehicle does stop, and also the shift lever is now difficult to shift fro and back into Park... Please advise.... Thanks for your time...

Good content. Always learning something new. Keep up the great content guys.

Im trying to fix an 04 grand Cherokee the 3rd break light works fine but the other 2 don't work. Ive checked the bulbs and the fuses, and im at a loss.

Thanks the yellow and orange wire was right on the money!!

Thanks for speaking English and explaining things simply

My break lights work but when I turn the car on they turn on with out me touching the break and when I push the break they won’t do anything sorry my English is bad but I hope someone understands me 🥴

My spoiler brake lights on but the car brake isn’t. Also my car no longer need to press brake to start engine anymore. Help pls

What if it's the brake light switch? My brake lights come on when I come to a complete stop! In other words, as soon as your foot presses the brake on pedal the lights are supposed to come on but mine doesn't!

All Pro, thanks for your help , mine was a second fuse box under the dash I didn't know I had. you saved the rest of my day and maybe another to the repair shop.

Short and very informative, thanks

What if my brake lights dont turn on when my headlights are on they work if my headlights are off

I have a 1961 Pontiac star chief. It has 6 tail lights.( 3 on each Side) only 1 works on the right hand side.it works on brake and turn Signal.any advice? Thanks

I have an 01 Tahoe z71 and when I press the break pedal my lights don’t come on but the yellow marker/ turn signal light comes one tho

Please help! 2007 jeep liberty. Third light works (when I press on break pedal) Nighttime, running rear lights work (same bulb as break light) No break light when pressing on break pedal (rear running lights will turn off) Break fuse is OK (#12, 15a)

Thanks for video. First time writing on here. I own an old Toyota Matrix 2004, basic model. There's an issue with the rear brake light on the right. Left side is fine. Tried to change the bulb. it's not that. Pushing break pedal only lights the left side. I also noticed that when the engine is off, and I turn the headlights to high beams, the lights in the back also light up - and both sides. - all the lamps! I know, this sounds like a mistery. Any advice would be aprreciated. Thx.

I have a 08 buick lacrosse. The brake lights only come on when the car is on. Is that a sign that the switch is going bad?

What if the dashlights parking lights an tailights aren't working. Fuses keep blowing?

My brake light only work when the lights are off

Could they have used a more rusted vehicle 🤔

2011 Jeep Grand Cherokee Laredo 5.7L. Rear passenger tail light out. Hazards work, brake lights work... Fuses good...bulbs good....socket bad? Just poured out a quart of water from the housing.

What if the tail light bulbs are working, but aren’t getting brighter when you press the brake pedal?

I've tried 3 bulbs for my passenger side brake light. Neither bulb worked. I tested the bulb socket with a multimeter. Having someone pressing the brakes I got needle movement with the OHM setting. No needle movement with the other settings. So there seems to be a current reaching the bulb socket. Is there something else I can try? The bulbs I tried are the ones given to me at the auto parts store for my car (08 Sentra).

My 2 sides aren't working when I brake

I checked every single fuse and switched them around, checked every solenoid and moved them around checked all bulbs, replaced the brake light switch. Still no brake lights. No 3rd brake light either.

Ha! I am currently having an issue with all of my lights on the back of my truck being out after installing a set of aftermarket taillights. I messed up and got the polarity wrong at first, once I figured that out I had no brake lights on the back of my truck. But you have pointed out fuses I have not checked and here I thought I checked all of them, I even replaced the brake light switch 🤦🏾‍♂️ going to the truck in the morning to check all fuses you pointed out in this video....BTW my truck is an 04 Suburban. Perfect YT timing with the video recommendation!!!👍🏾

Do I have to disconnect the battery if I need to “get in to the terminals” with a pair of pliers? My connection is bad but I think the prongs are just pushed in.

2007 Caddy Escalade . . . Installed LED Tailight / Brake Turn Signal fixture it was working for many years . . . TODAY . . . NO Brake Lights . . . T. S. work fine . . . EmerG Flashers work fine

My 99 ranger is giving trouble with the brake lights…. I’ll follow the vid and report back ! Great info !

My brake lights came on with the headlights but did not light up when braking. my traction control light was also on. I had a blown fuse.. replaced it with the spare in the fuse box and no more traction light and my brake lights working again. I hope I haven't been driving with no brake lights all this time

My bulbs actually workc when on the 'on' setting, they just won't work when I press on the pedal.

Now what if all of this doesnt work

i have a 06 honda cr-v ex sports 4wd my right side brake light want work when my lights are on but when they are off all 3 my brake lights work can you tell me what to do i done replaced them to see if that work still nothing why the lights are on can you please help

One running light and brake light 2001 Chevrolet silverado 2500HD right side only yes I definitely checked all the wires but on my tester not getting it to show voltage when its grounded and touching wires one at a time yes the bulb is good but that relay on the fame I may disconnect every one and inspect th4 harnesses and install them when finished

What if my break lights work but won’t stay in when my lights are on?

Would love to see this for a 2016 Accord

Why is it you ask about a specific yr make and model you guys always show a different yr or something not even lose to what you need to know ok w anout

Hello I have a 2006 Dodge Ram 1500, I have no lights on the right rear side of my truck. the turn signal, brake light and reverse lights work when turned on, but just turning the switch on there is no lights on the right side

Hello Sir, thanks for this video it is really informative. BTW, I would like to ask what causes a brake light bulb to short when it gets in contact with the vehicle body(which is normally grounded) and the brake light switch is not active(pedal is not depressed) but the key is on.. I would greatly appreciate your feedback.

You guys are lifesavers. Thanks again.

I have this problem where my rear right bulb stays on but does not blink when I activate the turn signal. Front right does blink though, it’s just the rear one. Can somebody advise ???

My roommate was driving last week while I was passenger. and we came upon a red light a lot closer than we anticipated. and ended up hitting the brakes pretty hard and slid for a couple feet. immediately following this incident the left rear turn blinker light stopped working. when you turn the turn signal on it makes like a double-time sound, but the right blinker works fine and I think both front blinkers work fine basically the rear left turn signal stopped working after a sliding break. could there be some sort of easy fix?

I have one brake light working, one not, one tail light working and one not. Both in the back, I’ve changed the light bulbs and it’s not that. What should I do next?

Well I have a brake light issue all my other lights work my brake lights and the circuit board are all brand new I replaced the switch every relay I can find I put the fuse in and my brake lights stay on and but they won't go off until I pull the fuse out I don't know if it's a connection issue because I Arc something underneath the dash and it blew out my feet my fuse and I replaced the fuse now my lights to stay on and it's driving me nuts I'm going bananas I have a power probe when I'm short and open draw 3,000 I think it's called and on the when I have it plugged in it's saying I have a short on the right side and on the left side of the fuse it says it's open

sip your beer EVERY time he says "ACKshull or ACKshully" .. you'll NEVER finish the video Hiccup!

I have tail lights turn single work emergency flashers work but my high mouth on trunk don't work or my break lights won't work had blown fuse replaced it still no brake lights checked the bulbs when I tried to get them out then brake lights came on but then went back out I left high mouth light unplugged so why won't brake lights stay working

I have a 2002 mercury grand marquis. I took down my visor on driver side. Cut a wire that was connected to it and Now im not gettin any power to my ac/heat panel. Nor is my clock workin. Please help!!

I have brake light signal works and when im braking it works, but no brake lights when i turn on the lights left side, what's the problem?

My Leer cap is causing a short. My left brake light is dim compared to the right. I thought it was the bulb and replaced the bulb but it is not the bulb. It might be the connection from the third brake light, which is dead, and the connection from the third brake light on the Leer Cap is connected to the left brake light. So it makes sense that something is wrong with this connection. I am trying to see if there is a way of correcting the problem. I have reached out to Leer two times to see if I can order a new third brake light for the Truck Cap and their assistance is non-existent. Any advice would be helpful, thanks.

What could be the reason my reverse lights aren’t coming on? They both went out at the same time and I’m stumped

Break Light only turns on when stopped completely! Help!

Well my problem is this = my tail light wiring was cut and I cleaned up the wires and the lights turn on but when I put my foot on the brakes only the passenger and the top light will light up but not the driver side , what should I do ??

Very complete and through. Problem solved. Thanks a lot

4:48 I don't understand that moment.Could you please explain me why you put pick on ground wire.I'd thought that the test lamp is enough for that.Normally if you touch the power wire with control lamp and if the other end is connected with the ground the light shoul be on.Maybe i have mistaken

In my car when the brake or signal light doesn't work the interior indicator light blinks fast on the side which doesn't work

How would I check reverse lights that are dimly on even when the car is off?

My question is if you have two brake lights on one side but one of them is out should you change the other one that isn’t nothing wrong with it

So to test a bad ground wire I have to have a positive somewhere hooked up and touch the ground wire? Love your vids

I wiggle my left side brake bulb then it works fine . I think the socket needs to be tightened up

what about grounds ???

Only one brake light is 3:55 working but botth taillights work???

what if my right brake light doesn’t work only when my night headlights are not on? it works when i turn on my headlights

Should I turn on the lights before I check the tail light fuses?

My tail light is not working at all

How much are mechanics charging for this kind of work ?

I'm working with a 2002 suburban, no brake lights. I'm trying to find the brake light switch, this is my first time being under the dash, I've owned it for 10-11 years without any issues. I've checked the bulbs and the cyclops and none are working.

Good man you just saved me from going into hyper mode with anger. I just bought 2 led brake lights and neither of them worked initially. I was fixing to tear my backseat apart to check fuses, then it hit me, flip the lights around. And just like magic they both worked. Thank you, thank you and thank you for the tips!

I need help I have a 2001 Pontiac grand am when I press on brakes my left tail light uses the left signal like if it was a brake light and when I release it the idle lights glow so it’s not the bulb and also not the circuit board I just bought it

The stop light and tail light are different fuses right?

Can I run a wire from right side that works to the leftsde

I keep replacing my brake switch and my brakes only come on sometimes, do you know what could cause that?

What scanner is that?, is that a pretty good one?

I disconnected the tow harness, to drop hitch when installing 2" shackles. Both bottom lights are now out.

Always enjoy your stuff

Question: are the vehicles you guys work on are your own personal, customers,etc?

Test light, I want those gadgets.

This video, while quite informative, didn't mention anything about diagnosing the "tail light" that is not working....

Thanks it was helpful 👍

I have a 2006 Silverado and all lights work but when head lights are one the break lights don’t engage, I replaced the switch and checked all fuses but the only way I can get them to engage is by shutting off my running lights, could it be the switch that controls the auto lights and on and off? Im so lost

Like your in depth to the point considered explanations 👍.There of great help on keeping car in top shape 🇬🇧 Greatings from Northern England

It's my taillights

👍👍👍👍Awesome

What if break light turns on but not the regular light ?

Really appreciate your videos!

Can u guys please do a tutorial on a 2011 camaro tail light dysfunction. If u need some info on my issue I can provide that as well I can’t find no videos on this issue

Thanks a milli

Yes

👍👍👍👍👍👍👍👍👍👍👍👍👍👍🙏🙏🙏🙏🙏👋✌

I backed into a post and busted my left rear taillight lens out. I thought I could replace just the bottom lens but that wasn't the case. The whole assembly comes in one piece and, thanks to this webpage, I found out how simple it would be to replace it. I ordered the new assembly and when it arrived, it took all of 20 minutes to change. The part that took the longest was getting the wiring harness plugged in to the new one. It just didn't want to co-operate, but I was finally able to get it done and I saved a bunch of money doing it myself. Thanks for your help. This is a very cool webpage.

Thanks for the info...

Fantastic