Electrical: Parking Lamp when brake is pressed (1951 Studebaker)

[61LaRk4dr]

It appears I spoke too soon when saying that I had all of the lights worked out. A few weeks back I was having problems getting the turn signal to work. They work great....only now I have a problem when I press the brakes. The drivers side parking lamp and the passenger side tail light light up. The drivers side brake light does NOT light up , the passenger side parking lamp does NOT light up. Before I had the problem with the signals I was able to get both brake light to turn on when the brake pedal was depressed. As far as I know, nothing has changed. The turn signal wire harness was already connected in the car when both the brake lights worked. I have attempted to remove both parking lights to see if that would fix the situation, but I still only get the passenger side tail light to work. The bulb on the drivers side is brand new and will work when the tail lights and the flashers are engaged.

[StudeRich]

If both Parking Lights and Tail lights work, that should elliminate a bad ground.

So it almost HAS to be in the Turn Signal Switch or it's wiring. Since installation, the contacts could have broken/failed.

Before the failure, were you able to see that the Stop Lights did both light with turn Sig. in Neutral and only the opposite one when one Rear Turn Light is flashing?

[RadioRoy]

It appears I spoke too soon when saying that I had all of the lights worked out. A few weeks back I was having problems getting the turn signal to work. They work great....only now I have a problem when I press the brakes. The drivers side parking lamp and the passenger side tail light light up. The drivers side brake light does NOT light up , the passenger side parking lamp does NOT light up. Before I had the problem with the signals I was able to get both brake light to turn on when the brake pedal was depressed. As far as I know, nothing has changed. The turn signal wire harness was already connected in the car when both the brake lights worked. I have attempted to remove both parking lights to see if that would fix the situation, but I still only get the passenger side tail light to work. The bulb on the drivers side is brand new and will work when the tail lights and the flashers are engaged.

Let's clarify some terminology, please. The better everyone understands the symptoms, the better the advice.

There are eight filaments affected, right and left of each type:
front parking lights - small filament
front turn signals - large filament
rear taillights - small filament
rear brake/turn signals large filament

Are the tail light and parking lights really the ones affected?

Or is it the front turn signals and rear signals/brake lights?

If the turn signals and brake bulbs are affected, that makes sense because they all go through the turn signal switch. It sounds like some of the wires got plugged into the wrong sockets.

If the parking lights and tail lights are affected, then that would be really weird, unless some of the bulbs are in the socket wrong..

[61LaRk4dr]

Let's clarify some terminology, please. The better everyone understands the symptoms, the better the advice.

There are eight filaments affected, right and left of each type:
front parking lights - small filament
front turn signals - large filament
rear taillights - small filament
rear brake/turn signals large filament

Are the tail light and parking lights really the ones affected?

Or is it the front turn signals and rear signals/brake lights?

If the turn signals and brake bulbs are affected, that makes sense because they all go through the turn signal switch. It sounds like some of the wires got plugged into the wrong sockets.

If the parking lights and tail lights are affected, then that would be really weird, unless some of the bulbs are in the socket wrong..

After taking a look, I am using light bulb 1154 (double filament) in the tail light sockets. I am using 1158 (double filament) in the parking lamp sockets in the front. Both the 1154 and 1158 have what I would describe as a shorter (smaller/brighter) filament and a longer (bigger/dimmer) filament. You are correct in that it appears the smaller/brighter filament is lighting up on the front drivers side and the brake light smaller/brighter filament in the back passenger side. So I believe it is the front turn signal and rear brake light that you were describing. When I pull the light switch out one click to the parking lamp setting the bigger/dimmer filament lights up on both front parking lamps. Both tail lights (bigger/dimmer) filament also light up at this time. I went through the wiring again to see if something was not matching up and was not able to find a mismatch wire. I will continue to look. What I find strange is that before I fiddled around with getting the turn signals to work, both brake lights were working. I now have the turn signals working but a brake light in the passenger rear and one in the drivers side parking lamp. Sorry for the lack of correct terminology, this is all a new learning experience. Wiring has always been a "black magic" in my mind, but we all have to learn sometime.

[altair]

Try this small test, turn the park lights on only and look at all the bulbs and see if one is brighter than the others. I had a similar issue that took hours to resolve where as the filament in the lamp had burned off and re-welded itself to the remaining good filament. This created a new circuit and with the turn signals actuated the dash lights and radio would flash. I hadn't touched any wiring therefore I didn't suspect a wiring issue. It actually took several says looking at the lighting before I noticed the one brighter bulb, I changed that one bulb and all was back to normal.

[rstrasser]

61Lark4dr;
I might have missed something in your note To me it sure sounds like the wire going to the front and rear turn signal on the left side are reversed.
Ron

[sals54]

Dont be too quick to discount a grounding issue. When you apply the brakes, more current is being passed through the system than a weak ground may be able to handle. Check your grounds again. I had to add grounds to both my tail light housings on my 56 Wagon to make the brake lights work.
It seemed that the tail lights would go on, but the brake lights would not. Then, by accident, while someone was holding down the brake pedal, I touched the housing to the bumper, and bang-zoom, the brake light came on. I added a ground wire from the housing to the body and that fixed both brakes and tail lights.
You can test this without taking anything apart. Use a wrench to connect bare metal on the tail light housing to the bumper, while someone is pressing the brake pedal. If it works, then all you need to do is add the ground wire.

[61LaRk4dr]

Try this small test, turn the park lights on only and look at all the bulbs and see if one is brighter than the others. I had a similar issue that took hours to resolve where as the filament in the lamp had burned off and re-welded itself to the remaining good filament. This created a new circuit and with the turn signals actuated the dash lights and radio would flash. I hadn't touched any wiring therefore I didn't suspect a wiring issue. It actually took several says looking at the lighting before I noticed the one brighter bulb, I changed that one bulb and all was back to normal.

Took a close look and could not see any variation in the brightness of the parking lights. or variation in the brightness of the tail lights. One thing to note, the tail lights were brighter than the parking lights. Should all four lights be the same brightness?

[61LaRk4dr]

Dont be too quick to discount a grounding issue. When you apply the brakes, more current is being passed through the system than a weak ground may be able to handle. Check your grounds again. I had to add grounds to both my tail light housings on my 56 Wagon to make the brake lights work.
It seemed that the tail lights would go on, but the brake lights would not. Then, by accident, while someone was holding down the brake pedal, I touched the housing to the bumper, and bang-zoom, the brake light came on. I added a ground wire from the housing to the body and that fixed both brakes and tail lights.
You can test this without taking anything apart. Use a wrench to connect bare metal on the tail light housing to the bumper, while someone is pressing the brake pedal. If it works, then all you need to do is add the ground wire.

Tried the wrench to bare metal and was still getting the front drivers side turn signal filament along with the passenger side brake light. I will look around to see if there is anything else possible disconnected somewhere.