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  #1  
Old 03-17-2009, 10:59 PM
Leah M Leah M is offline
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Why is my car's brake light not working?

I'm taking it into a shop tomorrow to have it looked at first thing in the morning, but I'd like to have at least some knowledge of what might be wrong with it, rather than go in uninformed.

I have a 1994 Honda Accord. The 'brake lamp' light has been going off and on intermittently, so I had a friend help me check if something wasn't working. The car just passed inspection two weeks ago and they didn't say anything about the brake lights, but that might have been a day where the brake lamp light didn't go on.

I checked tonight and the regular lights work on both sides. The brake lights on the left side work fine. Not a single brake light on the right side lights up when I press on the brake.

Seeing as the autoshop just checked me out for inspection I don't THINK it's a fuse or a problem with the lights themselves, though I'll have them check that. Since it's ALL the lights on the right side when I press the brake, what else might it be?

Loose wire? Corroded socket? Brake switch needs replacing? Suggestions / input are appreciated.
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  #2  
Old 03-17-2009, 11:29 PM
jasonh300 jasonh300 is offline
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Quote:
Originally Posted by Leah M View Post
I checked tonight and the regular lights work on both sides. The brake lights on the left side work fine. Not a single brake light on the right side lights up when I press on the brake.
How many different bulbs are on each side? Usually there's not more than two. Before you pay anyone to do anything, you should probably check to see if the bulbs are loose. You might have one burned out and the other isn't making good contact. You probably wouldn't get the warning light until both lights on one side aren't working. But that's not for certain.

You might have someone hold down the brake and bang (not too hard) on the lens and see if the light starts working or if you get a flicker.
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  #3  
Old 03-17-2009, 11:41 PM
Leah M Leah M is offline
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I don't know if it affects anything or not, but the problem originally started when the weather got really, REALLY bitterly cold. At the same time during the cold spell, my turn signals would flicker VERY rapidly when in use, but this problem stopped. Also, the lights would click when I turned them on, but this also stopped. Neither of those things have been an issue since.

From then on, the 'brake lamp' light would go off and on at times, without really any set pattern. Sometimes I'll be driving for a while, and then suddenly it'll go on. Sometimes it goes on right as soon I get in the car and press on the brake to change from Park to Drive. For a while, as long as someone was sitting in the passenger side, it wouldn't go on.

Maybe more indicative that something is loose? I'll try experimenting when I get home (at work, currently) with what you suggested, jasonh300.

Last edited by Leah M; 03-17-2009 at 11:43 PM..
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  #4  
Old 03-17-2009, 11:51 PM
lobotomyboy63 lobotomyboy63 is offline
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IANA mechanic. Hard to say, though: if it's the original brake lamp, I wouldn't think it too weird that after 15 years it's failing.

They aren't that hard to replace on most cars. I'd check your owner's manual and maybe take a trip to NAPA or similar. I don't think I'd pay a mechanic beaucoup bucks before taking a shot at it myself, and I'm nobody's idea of a handy guy but I have successfully replaced them before.
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  #5  
Old 03-18-2009, 12:05 AM
Leah M Leah M is offline
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lobotomyboy63:

I'm really an idiot when it comes to cars (well, maybe not as bad as I could be), but my mother is visiting on Friday and I know she knows how to replace fuses / lights, so maybe I'll have her take a swing at it before I hit the mechanic.
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  #6  
Old 03-18-2009, 12:19 AM
lobotomyboy63 lobotomyboy63 is offline
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Quote:
Originally Posted by Leah M View Post
lobotomyboy63:

I'm really an idiot when it comes to cars (well, maybe not as bad as I could be), but my mother is visiting on Friday and I know she knows how to replace fuses / lights, so maybe I'll have her take a swing at it before I hit the mechanic.
I replaced them on a Ford Tempo I had. IIRC I had to remove from the inside, not the outside. It was not like screwing in a household bulb. They had little plastic "wings" that would spring into place. Not hard.

The hard part is probably getting to the bulb, but I imagine your manual shows how. I put in 1994 Honda 4 DR LX 4AT and got this from Majestic....

http://www.hondaautomotiveparts.com/...LLIGHT+%281%29

There are owners' clubs on line that you might check out (I have a Honda, which is how I found out about Majestic). You might also like to find accessories....

http://www.handa-accessories.com/accord03.html
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  #7  
Old 03-18-2009, 01:31 AM
Leah M Leah M is offline
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Thanks much for the info. I was trying to find a diagram online and was coming up short, so that's a big help. I'll consult the manual when I get home, too.
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  #8  
Old 03-18-2009, 02:03 AM
missred missred is online now
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I don't remember whether it was the same with my Accord, but in all of my GM and Ford vehicles since the 80s, when the interior turn signal indicator does the rapid blinking thing, it means that you have a bulb that needs to be replaced. That's a relatively easy and inexpensive thing to try before running up a bill at the garage.

If that doesn't work, then you'll want the circuit to be tested for continuity. This isn't too hard with a tester from the auto parts store. Some auto parts stores will also offer this test free. Even if you don't have the knowledge to fix it yourself, it should at least give you a ballpark idea of what you'll be looking at or eliminate something when you take it to the mechanic.

Last edited by missred; 03-18-2009 at 02:04 AM..
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  #9  
Old 03-18-2009, 02:23 AM
Leah M Leah M is offline
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missred:

Thanks for the tip. I did have to have one bulb replaced (one of the amber lights in the back) when I had the car inspection done, and the turn signals have worked fine since then, so maybe the brake light's really gone kaput too, between now and when I had the car last checked.
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  #10  
Old 03-18-2009, 05:20 AM
longPath longPath is offline
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Leah

By "brake lamp light", do you mean the idiot light on the instrument cluster?
It will come on intermittantly if the level of brake fluid in the resevoir on the master cylinder gets too low.
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  #11  
Old 03-18-2009, 09:42 AM
Gary T Gary T is offline
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If any brake lights work at all, it's not a fuse or brake light switch.

Are you quite certain there's more than one brake light per side? I ask because my info shows only one brake/tail light per side in the wiring diagram. When only one light fails to operate, 95+% of the time it's a faulty bulb. A failing bulb can go back and forth between working and not working for while.

If there are indeed two or more brake lights on that side, and they consistenly fail together and work together, the odds of it being faulty bulbs are astronomical. In that case, the top suspect would be the brake light failure sensor.

Faulty wiring and faulty sockets are possible, but rare.
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  #12  
Old 03-18-2009, 02:36 PM
Leah M Leah M is offline
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I wasn't sure if there were one or two brake lights on each side, so I doublechecked when I went home. It's just the one.

I actually inspected them more closely and I noticed that the brake light that doesn't work has condensation / moisture on the inside of the lens. I can visibly see water droplets.

I had my friend press on the brake for me, and I very VERY gently tapped the lens. The 'brake lamp' light (yes, the 'idiot light' on the console) shut off, and the brake light came on. It flickered once or twice, and has been working ever since. The 'brake lamp' light came on once more for a minute, but the brake light worked. The next time I turned the car on, the 'brake lamp' light stayed off, and the brake light is working fine.

Should/can I do anything to fix the condensation problem if it's working okay? I'm wondering if this is why the problem started with temperature changes.

Last edited by Leah M; 03-18-2009 at 02:36 PM..
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  #13  
Old 03-18-2009, 02:51 PM
Gary T Gary T is offline
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Moisture in the lens assembly can lead to corrosion in the socket. Here's what I would do:

~Remove the lens assembly and take all the bulbs out of it.
~Get the inside as dry as possible. Blow out with compressed air, leave out to dry (overnight?) in a non-humid place, whatever works.
~Carefully inspect the lens to see how the water got in, then seal any cracks, holes, or faulty seams with clear silicone-in-a-tube.
~Alternatively, buy a new (or used) lens assembly.

~Carefully inspect the socket for any signs of corrosion. If there is corrosion, replace the socket. Coat the inside of the socket, including the terminals, with silicone grease.

~Replace the bulb.

The above should yield a permanent fix. Now, if the socket's not corroded, just replacing the bulb may solve the current problem. However, if the moisture issue isn't dealt with, there likely will be further problems down the road.
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  #14  
Old 03-19-2009, 02:45 PM
Leah M Leah M is offline
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Thanks, I'll definitely look into all that. Much appreciated!
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  #15  
Old 03-19-2009, 05:50 PM
chaoticbear chaoticbear is offline
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Or it could just be something totally bizarre - in my car, I had a big wiring mishap as a side effect of a tire blowout - they worked fine after my dad reattached wires, but now I have to pull back about a quarter of an inch on my bright-light stem while pressing the brake pedal to make the brake lights work. Same issue with the cruise control - I wad up a napkin and stick it behind it when I go on trips and need it.
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  #16  
Old 03-23-2009, 04:24 AM
Leah M Leah M is offline
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Well, mystery solved... I think.

I found the panel that opens up for that particular light. One of the latches is broken, allowing condensation to form inside the lens area. Plus a wire is held in place with some electrical tape.

Thanks for all the help in this thread, I've learned a bit more about cars as a result.
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  #17  
Old 03-24-2009, 09:31 PM
lobotomyboy63 lobotomyboy63 is offline
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Quote:
Originally Posted by Leah M View Post
Well, mystery solved... I think.

I found the panel that opens up for that particular light. One of the latches is broken, allowing condensation to form inside the lens area. Plus a wire is held in place with some electrical tape.

Thanks for all the help in this thread, I've learned a bit more about cars as a result.
Innit great when you don't have to go to the hassle and expense of taking it to the dealer? Glad to hear you were able to fix it. Woot!

ETA: Check Majestic if you want to replace the latch.

Last edited by lobotomyboy63; 03-24-2009 at 09:34 PM..
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  #18  
Old 03-24-2009, 09:49 PM
elfkin477 elfkin477 is online now
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Quote:
Originally Posted by Leah M View Post
Well, mystery solved... I think.

I found the panel that opens up for that particular light. One of the latches is broken, allowing condensation to form inside the lens area. Plus a wire is held in place with some electrical tape.

Thanks for all the help in this thread, I've learned a bit more about cars as a result.
Keep this knowledge in mind - I had a similar problem with one of my car's turn signal lights, and every bulb I put in it slowly failed, functioning more and more erratically, within six months no matter what we tried to keep things dry. On the plus side, I got really good at replacing the bulbs.
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