Headlight relay kit

[6.9poweredscout]

Not sure...but do a write up!

 

[drinkypoo]

The LMC product I'm ordering is just the harness and you need two relays to complete it.

ETA: The more I look at the wiring, the less inclined I am to buy the harness and just get the relays and fuse holder for this. I have plenty of wire and connectors. My questions now are:
can I use #12AWG wire to cut and splice to the relays,
can I use 30/40amp AGT relays instead of 20amp relays, and
is a 20amp fuse sufficient for protection using the above materials with stock headlight bulbs?

Well, maybe LMC is carrying something different now, but what they had when I was ordering included relays with connectors to match, one female headlight socket and two male ones, all wired up more or less plug and play. You had to supply power from somewhere. And there's no fuses. Hmm, OK, I looked in the catalog, and no, they're carrying the same POS they were carrying. And what's most annoying about it is that it doesn't use standard Bosch-layout relays like everything else. They are practically falling out of trees, if you need a replacement. They're in almost everyone's cars, so you can get them out of any junker or anyone's parts box.

I have a 10A fuse for each of my highs and lows so a 20A fuse should cover both sides. But I like having separate fuses, because if need be you can run on your brights if they have their own fuse. Not something I'd like to do on the road, but it would be OK offroad.

#12AWG is overkill, so yes, you can use it. And you can use 30/40 amp relays if you want, but 20 amp relays are plenty. you can get far better headlight connectors at the local parts store than what came in my LMC kit if there's anything wrong with either of yours. Whatever you do, use standard Bosch-layout relays, whether you use sockets or not. #1 reason not to use the LMC kit, even if you're not using the connectors. Two relays, some insulated female spade crimps, some butt crimps (I prefer solder but anyway), one ring crimp to the starter relay hot side for power, some wire, some fuse holders with fuses and a stripper/crimper is the total list of stuff you need to pull of this job if your headlight connectors are good. You can pull it off cheaper with circuit protection.

 

[youngunbd]

The relays I linked off amazon are great, with nice beefy wire in the plugs, getting your own headlight connector, some wire and heat shrink and you'd be set

 

[mjs2011]

So what seems to be the consensus here? Custom wiring and splice in to the factory wiring to provide power from relays, or use the connectors that replace most everything?

Sent from my SCH-I535 using Tapatalk

 

[mu2bdriver]

Thanks, guys. The reason I mention the 12AWG is that I have miles of it from when I re-wired the house. Now that I think about it, I probably even have some 12/3 Romex that I can use, throw a loom around it and make my own harness that way. Even though I never intend to sell the truck, I don't want it looking like a hackjob.

Thanks for linking those Amazon relays - I bought them last night. They appear to use standard Bosch-style numbering and having a few extra is never bad.

I'm going to take my time on this, go through the truck's headlight wiring and review the FTE link someone posted earlier.

Thanks again!

 

[drinkypoo]

I hope you're talking about stranded wiring. If so, carry on. If not, reconsider. I would strip apart a computer power cord and use that before I would use solid stuff. Come to think of it, reusing some of the zillions of PC power cords I have around might be a nice way to replace the cables on the wheel sensors on my A8

 

[mu2bdriver]

Right after posting I went to check out the Romex and it is solid so I'll use the other stranded 12AWG I have. Good reminder!

 

[riotwarrior]

Right after posting I went to check out the Romex and it is solid so I'll use the other stranded 12AWG I have. Good reminder!

House wiring is for homes...not automotive!

Use the correct materials or do not do the job.

Al

 

[mu2bdriver]

How are the two different?

 

[6.9poweredscout]

2 things that **** me off when i work on a vehicle. 1. scotch locks. 2. wire nuts. ugh, not the right stuff to do the job.

 

[laserjock]

How are the two different?

Mainly the insulation and possibly the size of the strands. Not a good idea to use house wire anywhere but in a house. A spool of heavy primary wire is not that expensive.

Scotch locks should be illegal.

 

[drinkypoo]

The house wire usually has an additional plastic coating on each individual jacket to make it easier to pull and for additional abrasion resistance. The strands are heavier which is an issue with repeated flexing but otherwise not. But they're both insulated with PVC, which releases loads of dioxin when it burns. In the USA, you're required to use PVC coating by code in most places if not everywhere. Hooray!

I personally like to cannibalize wire from other autos when I can get away with it. you know, reduce, reuse, recycle

 

[mu2bdriver]

Interesting. I'll just buy a spool of automotive wire and be done with it.

My original line of thinking was that for the length of wire that I'd be running, ~30' tops, the resistance would have been about 0.04 ohm so heat from the current shouldn't have been an issue. Compartment heat would have been another thing and was a variable in my mind, along with vibration and insulation of the wire. Using stock 9004 bulbs on the P29T base would draw about 8 amps total and between 90 and 130 watts (low/high) total so the difference between wire designed for AC and wire designed for DC shouldn't have proved to be significant. I don't know what the difference in strands/diameters/etc. is between the two wires but for constant DC loads, I imagine that surface area to be irrelevant.

If I'm way off-base on any of my original thinking, I'm sure others would like an explanation frpm those with a better understanding of the subject.

 

[Bashby]

I used a circuit breaker to power my relays instead of fuses.

 

[Nut Tree]

I ordered the LMC kit and an extra relay Friday night. Now I wish I would have built my own. Oh well, its not that big of a deal, I guess - would have been nice to save $20 and have common relays though.