Headlight terminal gets hot?

Electrical issues
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mcraeav
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Headlight terminal gets hot?

#1

Post by mcraeav » Sat Aug 01, 2009 12:45 am

Should the switch terminal where the headlight and tail light are connected to on my 62 FLH get hot when the lights are on and engin not running? I had a problem with my tail light not working and had to run a seperate wire from the switch terminal where the headlight gets its power and noticed that the terminal gets hot enough that I can't hold my finger on it after the lights have been on for about a minute.



Panacea
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Re: Headlight terminal gets hot?

#2

Post by Panacea » Sat Aug 01, 2009 12:53 am

Could be you have a bad connection, more resistance, more heat. Mike

mcraeav
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Re: Headlight terminal gets hot?

#3

Post by mcraeav » Sat Aug 01, 2009 2:36 am

That makes sense because I had to wiggle the terminal to get it to work. I ordered a new switch but it has 6 terminals and haven't had time to figure it out yet.
I did disconnect the wire that goes to the headlight and it shows continuity to ground; is that right? The headlight works but the tail light did not until I ran a seperate wire to it.

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Re: Headlight terminal gets hot?

#4

Post by awander » Sat Aug 01, 2009 2:44 am

The headlight bulb filament has a very low resistance, so that is why you measure continuity to ground on teh headlight wire. Disconnect the bulb and you should measure infinite resistance on that wire to ground.

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Re: Headlight terminal gets hot?

#5

Post by FlatHeadSix » Sat Aug 01, 2009 3:10 am

Mark
It's just like I told ya about checking the idiot lights on the dash, you can NOT really test the circuit (sockets) until you remove the bulbs. As Andy said, you are reading the resistance of the filament in the light bulb when you test it with your ohm meter, it gives the appearance of a false ground reading.

Pull ALL the bulbs and test it again, you should show an open circuit (no resistance) when taking a reading between the switch terminal for the light connection and chassis ground (switch turned OFF when taking this reading). Your terminal is getting hot because you have a short someplace, either in the socket or along the wire somewhere.

You may have to remove the wires from the ignition switch terminal and test them independently, first the headlight and then the tail light. I would almost bet that you will find the socket in the tail light, or the wire leading to it, is grounded out somewhere.

mike

mcraeav
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Re: Headlight terminal gets hot?

#6

Post by mcraeav » Sat Aug 01, 2009 2:43 pm

I also noted that there is a .25 volt draw on the battery positive wire when everything is turned off. Does that sound like a short also? I replaced the voltage regulator and still the voltage draw of .25 v.

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Re: Headlight terminal gets hot?

#7

Post by mbskeam » Sat Aug 01, 2009 6:17 pm

years ago I had mine get hot and fry the terminal right off the switch...
so I put in a new one, but if you look at the wiring diagram you will see that lot of load goes to one terminal.
I move the lights to a different spot to even out the load.
use a multimeter or test light to find the hot terminals when the switch is at the 2nd position......

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