Turning signals: Working - not working - working...

[Uncle-Pekka]

Well,

Not a joke, but some infrequent problem. Some time ago the turning signal on my D24 quit working. I noticed the relay under the dash was a bit hot. I replaced the relay, and the signals were working again. Then, after a couple of days the signals were not working when I was driving. Now the relay seems to be Ok, but I cannot find any other visible (or measureable) fault either. Parking lights are working, but not the signals. I suspect there is a bad ground somewhere, but how the heck I do find the spot?

Has any of you had similar problems?

Is there something basic I failed to check?

[Norm's Coupe]

Check the feed wire for the signals under the dash. Should have separate wire going to the hot source, usually the ignition switch. Mine did that sometime ago and it turned out to simply be a loose connection in that wire.

[Bodacious]

Yes, a bad connection, faulty component or anything that causes excessive resistance in the circuit (including grounds) could be at fault. If nothing is obvious, you'll just have to go through the entire circuit checking connections, checking resistance of wires and components, etc. Have you tried another flasher?

Fixing electrical stuff is easy! It's finding the problem that can be a pain!

[greg g]

Grounds are at the bulb. Any corrosion in the bulb to socket or the housing to body will cause additional resistance. The flashers are finiky about dealing with extra resistance or low resistance, in the case of a bulb not lighting. If a bulb is poorly grounded and not iluminating, the flasher reads it as a blown bulb, and that the circuit doesn't have enough resistance to heat the bimetalic strip in the flasher so it stay open. The flasher runs of a bimetalic strip, so if it doea't get hot enough it won't open and close causing the flash.

[Uncle-Pekka]

Thanks for the advice, gentlemen!

The initial reason was obviosly several bad contacts and bad wiring at the front parking lights. Unfortunately the sparking at the bad spots obviously blew the flasher as well. I cleaned the bulbs, contacts and replaced several wires and the flasher relay. Now I am good & legal again (to go fast, turn left...)