Intermittent lights

My headlights started doing something weird. They cycle on and off slowly, like every 30 seconds. I hear a clicking sound each time they turn on and off. Any ideas what the problem is?

 

Yep that is the circuit breaker behind the head light switch. It is there to protect the switch against a short or overload. Your head light wiring has a very high resistant short somewhere.

 

Have you added anything electrical wise lately that may be causing an extra load on the circuit breaker?

 

You may recall that I installed a new turn signal switch (and new flasher) in the last week or so. This is first time I have tried to use the head lights since then...

 

Yep I do remember. That would not do it because they are not ON when you are testing the head lights. Hit the dimmer switch and try your lights again. If the circuit breaker holds, then determine if it is high or low beams causing the problem.

 

Maybe it's the circuit breaker itself, they can get tired.

 

Could be, but if you hook an amp meter up directly next to the circut breaker, you can easily check the draw to see if it's more the the circut breaker rating. If it is wired correctly, I'm with Walt on the short. Isolate high/low beams first, and then disconnect the right/left terminals.

 

I remember not long ago, we have a member that installed a new head-light switch that was shorting out internally. The park/tail (first notch) was fine but shorted when all the way out for head-lights.

 

Lights go on and off in both postions (head light or park light) of the light switch, high/low beam switch setting seems to have no impact.

 

A few years back I had the same problem on my Commando, tuned out to be loose connections.
Tighetened up the nuts holding the wires to the circuit breaker.
You might want to check for frayed/corroded wires in the rest of the light wiring system.

 

PeteL mentioned a tired circuit breaker and this is a possibility. However if the wiring for the park lights has a problem and is connected to the wrong terminal on the light switch then it could pop the breaker when pulled to both positions.

 

Truly Intermittent lights. Lights started working...for awhile...now back to not working correctly. Will remove and inspect switch and wiring this weekend when I have time.

 

Look for a bad ground.
Or it could be that junction block on the drivers side fender.

 

Won't be a bad ground if it is popping the breaker. A bad ground would mean open circuit which does not draw current so it wouldn't pop the breaker. On the head light switch (if stock) you should have a wire that comes hot on the first position pull and that should turn on the front marker lights and go off on the second pull. Also on the first pull you will have another terminal that powers two wires that turn on the dash and tail lights that will stay on during the second pull (all the way out). Some switches have a letter near the terminal like H for head lights P for park lights and T for tail lights.

 

Wiring looks pretty good (below), how can I tell if the breaker mounted in the back has gone bad?

 

I only have a little Greenlee mutlimeter (DM-20). It does not look like it can measure 30 amps (settings 2000u, 20m, 200m).

 

If you haven't checked already, look at your bulb sockets at all the lights. Also follow the lighting wires and look for anything that may be a problem. Like butt splices, any connections not making up well will cause a load and trip the breaker.

 

Heed Howard's post as that breaker has probably been in there a long time and should be replaced for safety reasons. If you elect not to do this then pull the switch to the first position and test with your volt meter and see which terminal has power. There should be only one terminal hot at the first position. Remove the wire or wires on that post and see if the breaker holds when you pull it to the last position.