Replace (junk?) Putco relays on Plug/play H4 Headlight upgrade? Or use RJM harness?
11-02-2013, 06:53 AM
#31
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The new harness plugs into the h4 plug that comes off of the pass side headlight. The old h4 plug on the drivers side goes unused. I taped mine up and left it behind the headlight bucket. So, now with the new harness installed, the power from your headlight switch goes to activating the relays in the new harness which sends direct 12v from the battery to the headlights. Before, all the drain from the lights was going through the headlight switch which over time causes it to oveheat and melt causing problems. Now that circuit is just used to power a relay which is a very light load and not a problem for the switch. Also, by the time the 12v going through the switch got to the headlights it wasnt always 12v anymore. The new setup gives you direct battery voltage which is up to 14v when the car is running. Thats why the harness upgrade alone can brighten up even your stock bulbs. I hope that makes sense. Im sure theres a sticky somewhere that explains it all better.
11-02-2013, 09:19 AM
#32
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So you plug in to the passage side using it as a on /off switch!Then plug both headlights up,while running another part of the harness to the battery for extra 2 volt or something like that? I bought a set deltas 2 year ago the dimmer switch flip out the low beams while driving at night....I needed to write to way I under stood it,didn't mean to but in.sorry!
11-02-2013, 10:41 AM
#33
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Yes, thats basically it. Also you need to connect the 2 ground wires to ground. If you have been running the upgraded lights on the stock harness for 2 years and are having problems with the headlight switch, its possible that it is bad, possibly melted. Mine was bad. I replaced it with a new one from ebay, around $15.
11-02-2013, 11:31 AM
#34
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Ok, I ordered the Ebay harness and the Ebay Autopals.
I've got a stupid question about relays.
In general, what's the point of having a relay vs. a switch? Main differences in uses? Now, I can see having a fuel pump relay, so you don't need to manually push a switch to activate power to the fuel pump. It just activates when the car is powered. But, why have a headlight relay? You're using a hand pulled ****/switch to activate a relay. Why not just close the circuit right from the headlight switch and turn the lights on? Does it have something to do with larger voltage used by headlights?
Actually, I think this explained it: http://www.rattlebars.com/avalanche/relay_basics.html
Yea, different current in the switch vs the real current in the more heavy duty relay.
So, in the original design the headlight switch is part of the closed circuit and tended to burn out, and also limit the amount of current that reaches the headlights? Like a bottleneck?
I've got a stupid question about relays.
Actually, I think this explained it: http://www.rattlebars.com/avalanche/relay_basics.html
Yea, different current in the switch vs the real current in the more heavy duty relay.
So, in the original design the headlight switch is part of the closed circuit and tended to burn out, and also limit the amount of current that reaches the headlights? Like a bottleneck?
Last edited by BimmerJeeper; 11-02-2013 at 12:57 PM.
11-02-2013, 02:35 PM
#36
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A relay is designed to transfer full battery current and amperage to the load (light, pump, fan, whatever) using a small trigger load from a switch. Switches tend to wear out when high amperage is run through them due to arcing at the contacts. A relay solves this by using a low-amperage trigger from the switch to complete a circuit from the load directly to the battery, bypassing the switch. Relays are designed to handle the load while most switches aren't.
As it's designed, the Jeep headlight switch has to complete a 150-200 watt circuit (headlights/running lights). Not only does this shorten the life of the headlight switch but it's also an inefficient way of completing the circuit because a lot of the amperage that's supposed to be going to your headlights is lost within the switch. By installing a relay, you reduce the load on the switch to just the running lights and the miniscule amount needed to trigger the relay (probably a couple watts, if that). Installing a relay will not only prolong the life of your headlight switch, it will make your headlights significantly brighter. Even without the H4 upgrade.
As it's designed, the Jeep headlight switch has to complete a 150-200 watt circuit (headlights/running lights). Not only does this shorten the life of the headlight switch but it's also an inefficient way of completing the circuit because a lot of the amperage that's supposed to be going to your headlights is lost within the switch. By installing a relay, you reduce the load on the switch to just the running lights and the miniscule amount needed to trigger the relay (probably a couple watts, if that). Installing a relay will not only prolong the life of your headlight switch, it will make your headlights significantly brighter. Even without the H4 upgrade.
11-02-2013, 03:15 PM
#39
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Have them for one year and they still look good,when I had the sealed beams I could leave them on hi an never bother drivers coming from the other direction.Now I can't.
11-02-2013, 03:20 PM
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Another use for a relay,I modified a Homelink remote control from a Chevy and with a relay I connected it to my high beams to open my garage door.Flash to pass.
11-02-2013, 09:57 PM
#41
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I've got a stupid question about relays.
Not stupid at all. Just a good, basic question. Everybody is a newb at some point. Everybody is ignorant, just on different subjects.
BTW, it's not difficult to make your own harness. There's a good write-up on it here. Even if you go store-bought, you may need to troubleshoot it someday.
11-02-2013, 10:18 PM
#42
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LMC truck: 36-3580 $29.95 about $40 delivered to your door. They have a wiring harness that will work also.
11-07-2013, 07:37 PM
#43
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Wait, the Autopal just arrived and say "For Off Road Use Only"
Is this going to be a problem for passing inspection?
Why are these aftermarket headlights not cleared for street legal lighting?
Should I return them?
Is this going to be a problem for passing inspection?
Why are these aftermarket headlights not cleared for street legal lighting?
Should I return them?
11-07-2013, 07:45 PM
#44
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11-07-2013, 08:01 PM
#45
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Really what kind of inspection do you get a to z everything between? Or is it a to b and said to z there your sticker?