Headlights always on...

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Mike Kieley
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Joined: Tue Oct 19, 2010 11:25 am
Location: Southwestern Ontario

Headlights always on...

#1 Post by Mike Kieley »

I searched the Forum archives, but couldn't find anything on this...

Reviving a '57 coupe after a 3-year sleep - when I connect the battery, the headlights are on, although the switch is not. All other light functions OK.
Any ideas?

Thanks,
Mike Kieley

Alan Klingen
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Joined: Thu Oct 21, 2010 9:57 pm

Re: Headlights always on...

#2 Post by Alan Klingen »

The first thing to check is if it is a problem with a part or a wiring mistake. You really need to get Joe Leoni's wiring books and see if the car is wired correctly in the first place. I use his books in the shop as a first check. If you are happy that the wiring is ok then take steps backward to follow the problem. See if when the lights are stuck on if you can select high and low beam. If you are stuck in high beam you might have the flasher stuck on. If you have both you might have a bad switch. The 356 wiring is very robust, did you have any work done that might affect the lights? Are the park lights also on?
First remove fuses and see if they go out with each fuse.
Do these first and then report back.

Alan

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Barry Brisco
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Re: Headlights always on...

#3 Post by Barry Brisco »

You need Joe's book for your car. Here is how to contact him (he no longer has a website, but is still taking orders):
Joe Leoni
12745 West 61st Avenue
Arvada, CO 80004
303.431.5764
joe@356electrics.com

Pre-A Electrical Schematics $65
A/T2A Electrical Schematics & Descriptions $85
T5 Electrical Schematics & Descriptions $85
T6 B/C Electrical Schematics & Descriptions $85
Professional Series (All 4 - Schematics ONLY) $160[

Schematics and Descriptions are bound separately for easy 'back-and-forth' reference. The Descriptions are printed on high-quality paper, comb bound, and fitted with plastic covers. Due to popular demand, the Schematic pages are now laminated. An added benefit: use a non-permanent felt-tipped high-lighter to make notes on your schematic while working. When you're done, use a damp paper towel and your schematics are as good as new.

Mike Kieley
356 Fan
Posts: 65
Joined: Tue Oct 19, 2010 11:25 am
Location: Southwestern Ontario

Re: Headlights always on...

#4 Post by Mike Kieley »

Thanks folks - I have most of Joe's info. Everything was working fine when it was parked and all other light functions, including hi/low beam work, so it seems that it may indeed be the switch itself (I suspected this, but thought I'd ask the experts first).

Thanks,
Mike

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Eric Cherneff
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Location: Victoria, BC

Re: Headlights always on...

#5 Post by Eric Cherneff »

There is a relay that controls flashing the headlights with the center horn button on a 356A. An unintended ground somewhere (steering column, horn button, etc.) would trigger this relay all the time. You could isolate it by removing the power supply to the relay (the relay is the one with white and yellow wires connected to it, under the dash near the glovebox) - it should be the red wire from the fuse panel or black/white wire from the horn relay. Be careful - this feed is "hot" and unfused all the time! If the lights are off after disconnecting, then you know your problem is with that circuit.
Eric Cherneff
1966 912

356 Registry database manager

Bruce Coen
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Location: Pittsburgh

Re: Headlights always on...

#6 Post by Bruce Coen »

I'll bet that Eric has it right. I had something similar happen with my '56.

bc
Bruce Coen
1965 Coupe #219262
2000 911 Cabriolet

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