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Headlight switch questions

BIGsexyatUSC

NAXJA Forum User
Location
Charleston SC
my headlight switch went out on my '94 XJ Country recently and i was wondering if you guys can tell me if this is a common problem (after a certain number of years)

I'm on my 2nd one that just recently went out.........also can anyone tell me where to find a "cheap" replacement online somewhere? Thanks in advance!

i've checked the ground and i dont' think it seems to be the problem because everything works except the headlights don't come on when i pull the switch all the way out.
 
The headlights are fine.......in fact, i can use the high beams but i have to "hold" them on (sort of like pulling the switch to change from brights to dims, etc but having to do it the whole time i'm driving to make the lights work)

I wouldn't be on this board asking for help if the solution was that simple.
 
I got real good at swapping out that switch a few years ago. About a 5 minute operation once you know the trick. The dealer couldnt do it until I showed them how, Duh.

Obviously I cant know the cause of your problem, but in my case it was due to using upgraded, "E-code", headlights. The switch has a built-in circuit breaker which will trip off under heavy load or when it heats up sufficiently. In my case the increased current load would slowly heat up the breaker and it would trip, then reset a few minutes later, continuing the cycle along with a burnt insulation smell. The other symptom is to put your finger behind the plastic knob and see if the metal plunger is hot.

If you have stock (junk) headlights this could still be the problem if you have a wiring problem causing increased load. I rewired the lights with #10 wire and a relay and the problem is fixed.

Good luck;
Shogun
 
Then it's not the headlight switch it's the dimmer switch. It's under the dash, operated by a cable from the lever on some models, others have a plug in relay.
 
I have the aftermarket H4 bulbs so that may very well be the problem. Could anyone tell me where exactly I can get a new relay? Also, is the relay the same thing as the wiring harness or is that something different altogether?
 
BIGsexyatUSC said:
I have the aftermarket H4 bulbs so that may very well be the problem. Could anyone tell me where exactly I can get a new relay? Also, is the relay the same thing as the wiring harness or is that something different altogether?
I don't think you have a relay, after you replace the dimmer switch, you would have to add a pair of relays. What happens is the dimmer switch will operate the relays, and the relays operate the headlights.
Dimmer switch advanceauto http://www.partsamerica.com/ProductDetail.aspx?mfrcode=GPS&mfrpartnumber=DS17&parttype=404&ptset=A
 
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BIGsexyatUSC said:
can you tell me what type of relays i would need to buy?
The same ones the sell for driving lights. You will need one for High and one for Low.
You will also want some 10# wire and and a 30amp fuse to use as a new power supply for the headlights.
Just thinking it would be best to run two fuses, one for high and one for low, that way if you blow one you will still have the other so lets say a 15 and a 25 amp fuse.
Optronics A715 two needed.
 
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langer1 said:
The same ones the sell for driving lights. You will need one for High and one for Low.
You will also want some 10# wire and and a 30amp fuse to use as a new power supply for the headlights.
Just thinking it would be best to run two fuses, one for high and one for low, that way if you blow one you will still have the other so lets say a 15 and a 25 amp fuse.
Optronics A715 two needed.
????

You don't run the high beams and the low beams together, so why would you choose a smaller fuse if running two relays than you would to run one relay? Fuse it for the load of the high beams and that's all that's necessary. 30 amps is too big, and 15 amps is too small.

Watts = volts x amps. Two high beams probably equal 200 watts. Divide that by 12 volts and you get 17 amps. For that load you should run a 20-amp fuse, or maybe a 25-amp tops. The fuse is to protect the wire, so you should size the fuse and the wire to match.

There is nothing wrong with running two relays for the safety of the redundancy factor langer1 mentions, but it isn't necessary to make them a different rating. I would run two 20s and be done with it. Or you can run two relays and protect them both with one fuse.
 
Eagle said:
????

You don't run the high beams and the low beams together, so why would you choose a smaller fuse if running two relays than you would to run one relay? Fuse it for the load of the high beams and that's all that's necessary. 30 amps is too big, and 15 amps is too small.

Watts = volts x amps. Two high beams probably equal 200 watts. Divide that by 12 volts and you get 17 amps. For that load you should run a 20-amp fuse, or maybe a 25-amp tops. The fuse is to protect the wire, so you should size the fuse and the wire to match.

There is nothing wrong with running two relays for the safety of the redundancy factor langer1 mentions, but it isn't necessary to make them a different rating. I would run two 20s and be done with it. Or you can run two relays and protect them both with one fuse.
Your right about the fuse size, but the main reason for running separate supply and fuses is so if one blows you still have either hi-beams or lo-beams, you don't loose everything.

It's not redundancy at all, it just two separate circuits for hi and low beams the reason being is you can ever loose both at the same time
 
The headlights are wired so that the full power supply goes through the switch - and that makes the power path about four times as long as it should be (and places a significant load upon the switch.)

While you're about it, I'd suggest getting a couple Bosch relays, and make yourself a harness for the headlights. Run the power through the relays, trigger the relays from the OEM wiring, and the power patch will go directly from the battery to the users (the headlights.)

This will also make the headlamp switch last a LOT longer, and it will make your headlights brighter.

5-90
 
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