Blinker works, brake light not, same bulbs?

92 Buick Regal, friend of mine got a ticket yesterday for slowing down to stop at a red light that turned green for a few seconds maybe before she noticed. She also received a fix it or else command, even though
she has 2/3 brake lights working.
Thing is, the bulbs are good, they signal, but step on the brake and they don't light up. So I assume they're on a separate wire. Have to buy a wire tester I guess and test them. Fuses all look good, just put new bulbs in and they work when you signal, same bulbs light up when you step on brakes (or they SHOULD light up but the left side isn't working).
So, any ideas of what else it could be? Also, is it illegal to have 1/3 of your brake lights not functioning??? She was so upset about this, she's a responsible driver and was stopping at a red light! I was so mad, was going to call the police and chew them out, but she didn't want me to. I don't get giving a 60 dollar ticket to someone who was stopping at a red light that turned green. I think she should protest it, but can't afford to miss work, etc.
Anyway, why would the brake light not light up the bulbs but the signal do light up the same bulbs? Got to be a bad wire?
Thanks Impy
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Impy wrote:

First of all you will have to determine which are the stop light bulbs and which are the turn signal bulbs. Are they the same bulbs? Figure that out and then post back here.
In Texas, USA, if it came from the factory, then it has to be in good shape and working. Different countries have different laws. In your country, I don't know.
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USA North Dakota here, and the car is a 92 she's owned for years. Just to clarify. And they are the same exact bulbs, big honking ones blinkers and brakes. I'm going to test the wires. Thanks
wrote:

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I think a 92 Regal has 4 bulbs per tail light.
# 1 & 4 are Brake, Tail & Turnsignal. # 2 & 3 are Tailight.
1 & 4 are double filament bulbs and it is possible for one of the functions to not work while the other works just fine.
Make sure the thrid brake light in the rear window is working too.
Try using a known bulb that is good in the socket that was giving trouble.
As far as the ticket goes that was a sharp eyed cop to spot a burned out bulb. Most of the time here in Chicago they pass you right by if you have a busted out light, missing front License plate. They even miss the cars doing 55 in a 30 zone.
Good Luck
harryface 05 Park Avenue 91 Bnneville
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Impy wrote:

Since the same wire carries current for both turn signal and brake functions and the turn signal works, it would be a complete waste of time to test the wire. More than likely, its a bad turn signal switch.
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check for corrosion on the sockets and bulbs
USA North Dakota here, and the car is a 92 she's owned for years. Just to clarify. And they are the same exact bulbs, big honking ones blinkers and brakes. I'm going to test the wires. Thanks
wrote:

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Two thirds is not 3/3.

Corrosion in a socket, corrosion at a wire can do strange things. Are they dual filament bulbs? If so, could be one filamnet gone or a filament crossing the remaining one. Replacing the bulbs can often correct strange problems not visible to the eye.

Absolultey. Not only that, if you have more than the minimum lights, the extras must work also. Ask any truck driver than had one marker light out and a cop that wanted to be a prick. Some trailers have double the required minimum, but all must work.

Lot of factors come into play. First, the cop was 100% legal in giving a ticket for broken equipment. Should he have given her a break? Some will give a warning, verbal or written. Some did not get laid last night and will take their frustrations out on anyone. Can't say what the situation was as I was not there.

Possible, Wires, sockets, bulbs, switches. A real PITA to track down. Had a similar problem on a truck at work a few weeks back, Replaced the socket and all is well. Good luck.
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More likely the switch on the foot brake, WBMG
mike

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Mike,
I may disagree with you on this one. The fact that the turn signals on both sides work absolves the wiring from the turn signal switch to the rear of the car, the bulbs and bulb socket of blame.
The original poster's writing is a bit unclear on the next issue. If NONE of the rear lights light when the brake pedal is depressed, I'd go with your diagnosis. Another possibility would be that the connector on the brake light switch has come loose or that the wire from the brake light switch through the harness and connector up to the turn signal switch is faulty at some point.
However, if ANY of the lights light up when the brakes are applied, the brake light switch is absolved of blame.
My diagnosis (if ANY of the ear lights light when the brakes are applied) is a bad turn signal switch. There is a set of normally-closed contacts for each side that, when closed, connect the brake light switch feed to the rear turn/stop bulbs. The contacts for one side may be defective.
Impy, can you clarify which, if any, of the rear lights light when the brakes are applied (including the high-mounted stop light)? That way we can narrow things down a bit. There should be 4 tail light lit - the one directly next to the license plate and the far outer one (same as the turn signals) on each side, plus the high-mounted stop light in the rear window (or on the deck lid rack if this car has that option).
Regards, Bill Bowen Sacramento, CA

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Surely. Basically, the only lights not working are the two larger bulbs on the driver's side but ONLY when they are BRAKE lights. They are indeed the SAME bulbs that signal for turns, and they work FINE when you are signalling. Therear window brake light works fine too.
I tested the wires and the tester flashed just like the signal and it is the SAME wire that should carry the current to the same bulb, and the tester didn't light up just like the brake light didn't light up, though it flashed when used as signal lights. I tested passenger side wires too, all fine.
I have already changed the flasher a few weeks ago as she was having some signalling issues, and it worked fine after that. I believe that flasher controls the hazards and signal lights. There is a similar flasher on the passenger side, not sure what it does, but I changed that too. No go.
So I hope that clarifies things. Weird that the same bulbs and same wire that signal for some reason don't send an impulse when braking. All the running lights work, we changed those a few weeks ago too.
It would be super if anyone can help me diagnose this, she really doesn't have the money to spare if she can help it.
(Oh, and the whole ticket thing I think was a misunderstanding on her part. It only counts if she doesn't get the lights fixed. So sorry. Man, I drove for like 2.5 years with a burned out brake light and finally changed the thing on my car. Felt like a criminal!)
Thanks again Impy William H. Bowen wrote:

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Impy,
Based on the additional info you've given I'm certain that the turn signal switch is defective. As I mentioned earlier, there is a set of normally-closed contacts (one set for each side) that connect the brake light feed to the turn/stop lamps when the turn signal switch is not set to the right or left turn position. The contact for one side or the other opens when you signal a turn, allowing another set of contacts in the switch to connect the flasher feed to the lights. The contacts for the left (drivers) side are bad.
As to the flashers, the flasher by the steering column is for the regular turn signals - the one on the passenger side is for the 4-way flashers.
To replace the turn signal switch you are looking at removing the steering wheel, the lock plate and some other small parts, the trim under the steering column, then the switch. I'd get a copy of the Hayne's Manual for that car (Haynes Book # 8258 - ISBN Number 0-0819-8800-4). Section 8, starting at Page 24, has the lowdown on what is involved. A couple of special tools shown in the book are necessary to do this job without damaging the steering column.
Regards, Bill Bowen Sacramento, CA

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Signal switch for sure.

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I'm not so sure about that. He says that only one of the two brake lights on the side in question is not working - the other is. That fairly well eliminates the signal switch.
--

-Mike-
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Mike Marlow wrote:

Switch power is routed through both right and left, front and rear wires separately. Power for the rear comes through the blinker module if the switch is switched. If the turn sig switch is not switched the power is routed from one of the brake light switches directly to the rear lights but still going through the turn sig switch. A broken switch could still blink the lights but not allow one or more brake lights to work. Its hard to explain. Take one apart and see how it works or find a schematic. They are all pretty much the same for dual purpose rear lights.
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That wouldn't surprise me. Is that switch pretty easy to swap out do you happen to know? Or could I just route a wire from the right rear to the left rear and splice it in to fire up the left side brakes? Cheaper&easiest the better at this point.
Thanks again Impy
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Impy wrote:

Its pretty easy to change out. I _think_ the switch is $98 from the dealer. But if its just a plastic part that is broken, superglue works pretty good on ABS. Or a soldering iron to melt the plastic back together again. Clean it up really well first. I fixed mine mine (Pontiac) that way about 3 years ago and it still works good. Take off the steering wheel - you should not have air bags on that car - right? Take off the column covers. The switch should come off with a few screws - I don't think that model has the clip spring, but I could be wrong. Then, replace switch. If it has air bags then take it to a tech - Don't mess with it. You might try cleaning the switch when it is off the column. Maybe its gunked up.
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Thanks everyone for your advice. Looks like a trip to the garage for us. I don't have the necessary tools, and by the time I would acquire them the expense may be about as much. Plus, hopefully the mechanic will know what he's doing. But then again, I don't know how much they'll charge for the job.
Anyway, I really appreciate the people in this group taking the time to help me out. You are all very kind to do so. I'd be lost without you! Can only find so much in a google search. Though faqfarm.com is an interesting site.
Thanks again everyone! This group rocks!
Impy
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lights
switch is

one of

through the

allow one

schematic.
If I'm not mistaken though, aren't both left rear brake bulbs in parallel with each other and in series with the directional switch? In that case if one left rear brake bulb lights, and the other does not, then it can't be the switch.
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