Why do my high beams shut off after a while?

[EarlyPorsche]

On my 66 if I am cruising at night with the high beams on they will shut off on their own. Sometimes in a second sometimes they will go for a bit before turning off. I can't figure out what the cause of this is but its very annoying. I can turn the low beams back on no problems but the high beams are not reliable. What could it be? This is on a 1966 912 chassis with a 1967 911 engine.

[slodave]

Overheating? Street lights do this.

[rusnak]

See if the highs are on a separate circuit. Pull the fuse or relay, and clean the contacts. Otherwise it's time to get out the ol multimeter.

[Walt Fricke]

If a '66 has anything like the kind of high beam switch that later 911s have (stalk on the left side of steering column, also controls daytime high beam flash), that's where I'd look. Those go bad. Contacts pit. Some servicing possible (file contacts, rebend springy contact arms with needle nose pliers so they make contact again). Not excessively expensive as parts go.

Long term solution is high beam relays so switch doesn't see such high amperage.

Walt Fricke

[HarryD]

What Walt said. Good thread on the topic here: turn signal switch quick fix pictures

[rusnak]

I have a '70 914-6, which uses a 911 steering column. Comparing the '70 to my '78 and my '84, the headlight switches look to be very different on the early cars. And on the later cars, the problem is the high beams stay on, or turn on by themselves.

The problem he's having with the '66 seems like it could be something else, like a loose connection, corrosion, or both.