Headlight troubles.
Lead Driver
Joined: Jul 2009
Posts: 6,477
Likes: 19
From: Sheffield, AL
The kit does at least have a separate power lead for each light, it's not a single lead wired across the bulbs in parallel. The bit about the connectors is right though.....I remember that the terminals were kinda like a packard style crimp. I popped the ones that connect to the headlights out and hit them with some solder.
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
That's not something I would install. But there's an easy fix. I picked up a fuse holder like the one shown below and put it between the battery stud on the solenoid and the hot feed to the relays.
Laughing Gas
Joined: Sep 2012
Posts: 1,100
Likes: 6
From: Georgia
The pictured kit, or one like it, is ok for a quick fix, or if you want to easily revert back to original for concours showing, but I wouldn't want to reuse my old headlight terminal on an daily driver.
I prefer to just clip the ends off and fit new terminals to connect to the relays, if enough length, or use non-insulated high temp butt connectors and heat shrink adhesive lined tubing to splice in to get to the relay.
Yeah, #14 would be fine between the relays and headlamps.
I prefer to just clip the ends off and fit new terminals to connect to the relays, if enough length, or use non-insulated high temp butt connectors and heat shrink adhesive lined tubing to splice in to get to the relay.
Yeah, #14 would be fine between the relays and headlamps.
Senior User
Joined: Dec 2013
Posts: 143
Likes: 0
From: Lyman, SC
This is the instruction sheet pulled from another site. I would interpret it to mean the red wires that connect to the battery positive are fusible link.
Senior User
Joined: Dec 2013
Posts: 143
Likes: 0
From: Lyman, SC
On the kits like the one linked, you only connect one of your old terminals/plugs to the harness. It then activates the relays. As such it means you only have almost no load on the original headlight terminal and wiring....we're talking maybe 100 milliamps (one tenth of one amp) for each relay max.
Elder User
Joined: Sep 2013
Posts: 551
Likes: 2
It's our Southern Hemisphere smoke you need to watch out for
Elder User
Joined: Sep 2013
Posts: 551
Likes: 2
Avoid cheap connectors and small wiring at all costs. Halogen globes love a good strong supply of current. As does any resistive load really.
For my driving lights on my 4x4 I built my own loom, using 8ga cable from the batt to a thermo fan power block I had spare ( check the wreckers yard for these, they take a single power feed through 2 x 30 amp slow blow fuses to 2 outputs) then to 2 30 amp relays to feed each light, with the lights earthed direct back to the battery. The wiring from the fuses onward and back to the batt was metric stuff I had it the closest it would be in imp. is 10ga.
With the lights running ( 2 x 150 watts) I only get 0.3v of voltage drop from the batt to the lights themselves. FYI if you want excellent driving lights, the FYRLYT units are superb
For my driving lights on my 4x4 I built my own loom, using 8ga cable from the batt to a thermo fan power block I had spare ( check the wreckers yard for these, they take a single power feed through 2 x 30 amp slow blow fuses to 2 outputs) then to 2 30 amp relays to feed each light, with the lights earthed direct back to the battery. The wiring from the fuses onward and back to the batt was metric stuff I had it the closest it would be in imp. is 10ga.
With the lights running ( 2 x 150 watts) I only get 0.3v of voltage drop from the batt to the lights themselves. FYI if you want excellent driving lights, the FYRLYT units are superb
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
I'm going to do something similar, although I'm going with a mid-90's F-series power distribution block. Has a 150 amp maxi fuse on the input to take the output of the 3G I'm installing, and places for several relays and fuses. I'll have one relay that will be key-on, and the headlight relays will be pulled in via that relay so you cannot leave the lights on with the key off. And, the heater blower's supply will be a relay there as well, so there'll be very little going through the interior fuse block and ignition switch.
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Laughing Gas
Joined: Sep 2012
Posts: 1,100
Likes: 6
From: Georgia
On the kits like the one linked, you only connect one of your old terminals/plugs to the harness. It then activates the relays. As such it means you only have almost no load on the original headlight terminal and wiring....we're talking maybe 100 milliamps (one tenth of one amp) for each relay max.
14ga will only give a 0.07v drop over 5'.
Senior User
Joined: May 2013
Posts: 327
Likes: 0
From: Flaherty, KY
If I read this correctly-- the factory headlight switch has ALL the headlight current going through it?? What about the high beam switch, does it act as a SPDT switch and switch the common (+12V) to the low beam to high beam circuit (and vice versa)? I assume this carries the whole load too?
I will add a relay to mine ASAP if this is the case. I have no issues yet, but don't want any either.
I will add a relay to mine ASAP if this is the case. I have no issues yet, but don't want any either.
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
Yes, the headlight switch carries all the current. And, while I've not looked, the high-beam switch has to be a SPDT and it has to carry the full load as well. But, I'll look tomorrow to make sure.
Anyway, makes you feel comfortable, right?
Anyway, makes you feel comfortable, right?
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