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Discussion Starter · #1 ·
Guys,
I'm having a problem with my new wiring on my car. When I turn on the headlights after about a minute it kills all the power and in 15 sec it comes back on.

What I have done to test it is, I've disconnected both headlights and she never pops the fuse/breaker with the switch on. Also, running one light at a time no problem also. My only thought is I used one ground to connect all of the front lights, could this be the problem?

The only fuse/breaker that came in the kit is the one from the alternator to the main power feed back to the battery. I'm assuming this is the one which is popping.

Any help would be great thanks,

John
 

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breaker

Some light switches have a built in circuit breaker, both lights are overloading one of the breakers. You can check the alternator to bat breaker with out a meter by turning on your lights until one breaker trips then holding your finger on the alternator breaker and you should be able to feel a click when the lights come back on. if it is the light switch breaker you should hear it when the lights come back on . with out Knowing how your system is wired it's hard to do a long range diagonosis, You might need to add a headlight relay. there are several diagrams here on HR in the electrical or on the WIKI information.
 

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You have a resetable breaker,or a relay problem.I'm just guessing that the wire size is to small.I put a head light kit in my sons Toyota an I was amazed at how small the wiring was.Small wire gets hot fast an causes the breaker to heat up and it shuts down,when it cools down it resets it self.Sand the area to bear metal where the ground goes.
 

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I think what you have here is a breaker that is rated below what your headlights are drawing. If you have a 20 AMP breaker and your lights together are drawing 25 amps then your breaker will heat up, pop out, cool down , and then reset again turning itself back on.
If you disconnected one light and the breaker did not pop thats telling you that the breaker,s rating is only enough to handle one light, not two.
You are probably going to have to use a headlight relay to overcome the high current draw you have with two headlights.( Tim and others here have suggested also.)
If you can follow the diagram i think you will solve your problem. If you have 100 w globes x2, thats 200 /12 = 16 amps current just for two lights. So if other circuits are also using the same breaker then it is overloaded. Ignition circuit maybe 10 or 15 amps. So there is 31 amps with lights and ignition.
Try the relay.
Al.
 

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Discussion Starter · #5 ·
Thanks guys the harness is a EZ-wire 22 circuit same as the painless one.
(I know not really the same) However, the switch does not have a breaker. What really confused me was I didn't install any breakers :) I'm assuming the fuse/breaker is the one which is coming off the alternator. It looks like a ATC Style Breaker which may only be 20 amps.

I forget but need to look if the ATC Style Breaker is on the alternator lead or the fuse block. Because if it is just only on the alternator lead It should not lose power on the whole car, correct? I could up the breaker size but concerned of melting my new ride. (btw it is a 69 camaro)

The relay idea is a good one but I guess I need two, one for high and one for low beams?

Thanks
John
 

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Discussion Starter · #10 ·
Guys just wanted to stop by and say the problem was the draw from the fan. So I added a relay for the lights and the fan and problem was solved.

Thanks
John
 

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Good job, problem solved easily :thumbup:Auto electricians wont be paid after all. A quote to rewire my 67 was around a week full-time and approx $2000. A good incentive for me who took well over three weeks with an EZY kit.
Al.
 

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Discussion Starter · #16 ·
I built it from an older Cadillac it puts out 140 and at idle 14 amps. The fan only spikes to 70 amp on startup running I think is draws around 30 -40 amps.
 

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Thanks Guys this information came at the right time. I'm upgrading to the Lincoln Mark VIII fan and that thing draws 70 amps:smash:

John
You'll need a good Alt. when you start adding Elect. Accy's.
The Mark VIII does pull about 70amp @startup. It's best to start it on Low then ramp up to High when needed using 2 Temp switches etc..

There're a few guys that make custom Harneses for it w/HD Relays/Fuse etc..
70A Power Module Relay Harness

Volvo dual speed relay kit

Mark VIII, Taurus, Two Speed fan relay kit.

Upcoming electric fan control kits.... - MonteCarloSS.com Message Board

DIY Diagrams >> http://www.davebarton.com/pdf/coolingfandiagrams.pdf
 

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Discussion Starter · #18 ·
You'll need a good Alt. when you start adding Elect. Accy's.
The Mark VIII does pull about 70amp @startup. It's best to start it on Low then ramp up to High when needed using 2 Temp switches etc..

There're a few guys that make custom Harneses for it w/HD Relays/Fuse etc..
70A Power Module Relay Harness

Volvo dual speed relay kit

Mark VIII, Taurus, Two Speed fan relay kit.

Upcoming electric fan control kits.... - MonteCarloSS.com Message Board

DIY Diagrams >> http://www.davebarton.com/pdf/coolingfandiagrams.pdf
Thank you for the info I was going to use a 70 amp relay setup. Here is what I drawn up.
 

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One thing you should add,if you read the link I posted from Watsons you will notice a section regarding the ignition switch and the suggested 70 AMP relay you can actually find those and the matching plug at your local Fry's Electronics.After I added the electric fan,electric fuel pump and A/C the original switch crapped out even though I added relays for those and the headlights,after a new switch and the 70 amp ignition switch relay the system has been trouble free.
 
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