An odd problem for you electrical gurus

[Marshall V. Daut]

I drove my 1928 Phaeton yesterday about 15-20 miles to check the carburetor switch progress. O.K. there. But last night I happened to look out of our 2nd floor kitchen to the carriage house driveway below and noticed that the car's rear turn signals and taillights were on, albeit rather dim. They are connected so that when the turn signal LED's flash, so do the drum light lights (duals). But neither was flashing; just glowing. I went outside to see if somehow the turn signals had been left on and had drained the battery during the intervening five hours. Surprisingly, the front flasher bulbs were not on and I couldn't get the signals to flash at all. Good headlights, even though the battery was a little low by then.
I disconnected the battery with the intention of checking the wiring today. Thinking that the turn signal head had shorted out internally, I re-connected the battery today and disconnected the turn signal head's power lead. The rear turn signal and taillight bulbs still were on! WTF??? No matter which position I moved the light switch, the lights remained glowing. I then removed the light bail and wires and checked that. Yup - the rear turn signal and tail light bulbs remained on, even though the power to them running through the light bail area was disconnected. In other words, no matter what I disconnected (except for the battery), those lights remained on. Now I was really stumped.
For no particular reason other than to see if the new carb still was functioning properly, I started the engine and revved it up a couple times. Upon shutting it off and checking the lights, they were now OFF! The turn signals function properly again. Super WTF???
Do you electrical gurus have any suggestions about this situation? No wires were touching metal to short out and everything was tight and clean. There is an alternator, however. I wonder if somehow the alternator was sending power through the electrical system due to an internal malfunction that was cleared up by starting the engine and revving it up. Otherwise, I am stumped for an explanation why this happened. I flunked 8th grade electrical shop class because I am a complete dunce when it comes to electrical issues. I have seen a great deal of them with Model A's over the years, but this is a new one on me!
Marshall,
no electrical competitor for Thomas Edison or Nicola Tesla

[Patrick L.]

My first thought was brake switch until you mentioned about how they started working again.
It seems like one of lifes little wonderments, but, I'd still take a look at the stop switch.

[Tom Endy]

I am thinking the brake switch stuck closed as well. When you started the car you may have put your foot on the brake and when released they became unstuck.

Tom Endy

[Marshall V. Daut]

Hmmm...I'll check, but I don't think the turn signal LED's in between the bumper bars are connected to the brake switch, too. I wired them 18 years ago to act together as turn signals, but if they do, in fact, operate together with the brake light circuit, you both may be right. Kind of odd, though, that the brake light switch would all of a sudden "stick" after 18 years. 'Could be, though.
I'll get back with an answer later. Thanks for the suggestions.
Marshall

[Smog Tech]

I agree with Tom. Check out the brake light switch.

[Marshall V. Daut]

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'Just checked things out with my wife standing behind the car while I pressed the brake pedal. Sure enough: the turn signal LED's went on when the taillight stoplights did. 'Coulda knocked me over with a feather! All these years driving this car and I had no idea that whenever I hit the brake pedal, the turn signal lights were also laminated. Ha, ha, ha,! But then, how WOULD I know this from the driver's seat?
I'll lube the switch plunger rod and pedal. Perhaps a little sludge or crud is holding them from returning to their neutral positions. At least now I don't have to worry about this electrical bugaboo stumping me again, should this condition repeat itself.
Thanks again, Guys! Why weren't you there to help me pass my 8th grade electrical shop class???
Marshall

[Patrick L.]

Glad it was something easy.

Those switches are easy to check/fix.

[Marshall V. Daut]

Yes, although I don't understand why the turn signals didn't work during that time. I have the wiring set up so that they are not cancelled out when the brake pedal is applied. Yet, IF the brake pedal or brake switch hadn't return to neutral, why wouldn't the turn signals flash? The headlights were strong, so the battery was not down low enough for them not to work.
I guess this might be one of those times when you don't question a "repair" that the car makes by itself. Everything appears to be back to normal - although I will cast one more glance down at the driveway tonight to be sure the taillights and turn signal lights are illuminating again.
Marshall

[denniskliesen]

When your turn signals are on for an extended amount of time your flasher will heat up and stop working. I'd recommend installing a battery disconnect switch and get in the habit of using it.... always when you get out of the car. I remember reading right here on Ford Barn about somebodies car burning to the ground when he stepped out of it for a short amount of time.

[Big hammer]

Originally Posted by denniskliesen

When your turn signals are on for an extended amount of time your flasher will heat up and stop working. I'd recommend installing a battery disconnect switch and get in the habit of using it.... always when you get out of the car. I remember reading right here on Ford Barn about somebodies car burning to the ground when he stepped out of it for a short amount of time.

X-2 about disconnecting the battery!

[Patrick L.]

I too like a disconnect, i just don't use it except for the winter.

Every time I get out of that car I check the ammeter.

[BILL WILLIAMSON]

ELECTRICAL problems can drive you NUTS! Like, feed backs, stealin' grounds, etc. Too bad we can't "see" what's going on. Chief taught me to VISUALIZE those "little men" runnin' around doin' stuff! MOST important is to get familiar with your WIRING DIAGRAM!
Bill Wirey

[burner31]

Took this question to my master electricians, they all three agree...ghosts.
Quite common in older cars.

[Marshall V. Daut]

N'yuk, n'yuk, n'yuk! SOIT-enly!!!
M.