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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: desi arnaz on March 26, 2011, 07:50:50 AM

Title: 4106 headlights
Post by: desi arnaz on March 26, 2011, 07:50:50 AM
my headlights on the 4106 will not turn on. i have tested all the breakers and they all seem to be good. i have jumped 12 volts to the headlight and they work so that would eliminate a ground problem.  any ideas?
Title: Re: 4106 headlights
Post by: zubzub on March 26, 2011, 08:38:36 AM
on my 'o4 the wires from the running to the headlights were badly corroded. over heated etc....replaced them all.  Also on the '04 (may be the same on the '06) headlights have no relay, just straight through from switch (which tires (burns out after awhile) to headlights.....via the hi/lo switch on the floor.  Which reminds me,  hi/lo foot switch failure is a common cause of no headlights on many older vehicles.  If your headlights work only on hi you know the probable answer.
Title: Re: 4106 headlights
Post by: gus on March 26, 2011, 12:22:26 PM
I agree with zub, my 4104 had many corroded wires and terminals in the driver's electrical panel which I replaced.

This is a good time to add a relay to bypass the HL switch and instrument panel.
Title: Re: 4106 headlights
Post by: desi arnaz on March 26, 2011, 12:30:49 PM
my hi low is on the dash and i have power to the on off switch in and out.
Title: Re: 4106 headlights
Post by: Fred Mc on March 26, 2011, 02:37:10 PM
On my 4106 I have two floor mounted "dimmer" type switches. One is the hi-lo and the other turns the lights off completely. Not sure what it was used for. If you also have that perhaps it is in off position.
Title: Re: 4106 headlights
Post by: 2xclutchin on March 26, 2011, 02:51:21 PM
Not helpful information, but FWIW the switch that shuts everything off is for on the road, helps trucks or other busses when they would pass to let them know they can come back to the original lane of travel safely. All big trucks have them i know that for sure. Sorry for the off topic.
Thanks,
          Mike
Title: Re: 4106 headlights
Post by: desi arnaz on March 26, 2011, 05:20:49 PM
no foot switches......only button on floor is for horn that i  installed
Title: Re: 4106 headlights
Post by: Barn Owl on March 26, 2011, 06:05:05 PM
QuoteOne is the hi-lo and the other turns the lights off completely.

If someone (RJ? anyone?) could verify this because my book is in the bus. The second switch was to turn on the fog lights which in turn, turns off the head lights. I have the lights but mine are not working. I cannot recall without looking if I have a empty hole or a toggle switch. Also, are replacement fog lights sill available?
Title: Re: 4106 headlights
Post by: Lin on March 26, 2011, 07:07:55 PM
If you have power on the headlight side of the switches and the lights work when hot wired, then there is a wire or connection problem in between the two.  You could use a tone generator to find where the break is.  If you find it to be untraceable, you could just run a new wire or as others have suggested, upgrade to a relay system.
Title: Re: 4106 headlights
Post by: desi arnaz on March 27, 2011, 05:23:40 AM
on the 4106 which circuit breaker controls the headlights?
Title: Re: 4106 headlights
Post by: zubzub on March 27, 2011, 06:17:10 AM
I you are hot at the switch I doubt your circuit breaker  is the problem as the circuit breaker would usually be upstream of the switch.  Do you have a wiring diagram for your bus?  You kind of really need one to fix these things properly.
FWIW the other area that might be a problem is downstream of the switch at the circuit panel, this is the rats nest of wires to the left of the driver's knee. 
Personally, after having a terrifying no lights experience on a 2 lane highway at night, I replaced all the wire from breaker to switch to circuit board to hi/lo to headlights.
Title: Re: 4106 headlights
Post by: desi arnaz on March 27, 2011, 06:24:36 AM
i have the diagram but have no idea how to read it.
Title: Re: 4106 headlights
Post by: desi arnaz on March 27, 2011, 09:07:51 AM
now i am really screwed  i put the red lead of my fluke on the positive side of the switch and the black to each of the headlight spades i get 13.5 volts to each spade.and it is not reversed on the meter.  any ideas?
Title: Re: 4106 headlights
Post by: Len Silva on March 27, 2011, 09:11:00 AM
Quote from: Fred Mc on March 26, 2011, 02:37:10 PM
On my 4106 I have two floor mounted "dimmer" type switches. One is the hi-lo and the other turns the lights off completely. Not sure what it was used for. If you also have that perhaps it is in off position.

I don't have the book but I do believe that one switch selected HIGH-LOW and the other one selected HEADLIGHTS-FOG LIGHTS.