Headlight wiring harness

[FAKKY]

Starting teardown of my 57 apache.
To remove the side fenders off truck need to remove the wiring harness (disconnect from back of headlights etc) ... but . Its likes its hardwired from a wire junction on inside of engine bay and split off to upper and lower headlights/parking lights. No way to simply pull off.

So I started thinking maybe take of from front ....... nope. That ring mechanism and light adjustment is a PITA and the harness cant be decoupled - its a straight run from the headlight back to the engine bay junction..,....

so ...... looks like i can only basically cut the harness from the engine bay side of the fender in order to pull the wiring through and then get the fender/side panel off ........... since I was thinking about rewiring with a kit later anyway think this is the route I will go ....... but just thought I would post before I find out there is an easier way for now

[dsraven]

i have taken a 57 gmc and a 58 chev apart but don't remember having to cut any wiring anywhere.
if you are going to rewire anyway it won't really matter much if you cut the wiring. I would actually suggest a new harness anyway because the old wire is sometimes not in the best shape or may not have the circuit protection a new harness would, new looks better anyhow.
maybe take a bunch of pics as you go along of different angles and especially little brackets and parts that fit together for support etc. these can be a huge asset later when you assemble the truck. some guys will remove parts and place them in boxes or bags along with the original fasteners for that part. label the box they go in and store the boxes. then, in x yrs when assembly takes place, those parts can be brought out in smaller bundles which are easier to deal with. cleaned, repaired painted, fasteners replaced with stuff that is same length etc. we all think, when taking apart, that we will remember how it goes together but then, x yrs later, it becomes a mystery and we end up guessing. I have a friend who is finishing assembly on a 54 gmc. those pics he took have been invaluable for him with regards to things like how the inner fender sandwiches with the front fender or how the wiring was run from factory.what knob went where in the dash, what style of bolts went in a certain spot or other small details. he actually said he wished he would have taken more pics of dissassembly and organised them in labelled folders on his computer for future use. a guy can usually figure it out or get things assembled by logic but a pic says a thousand words.

[FAKKY]

Thanks raven.
I think it's actually meant to be just a quick disconnect behind panel in engine bay .... thin PO just hard wired it though and soldered it. So I cut it.

Curious on what people recommend for good wiring harness for front and rear lights.
I'll have the wiring harness from the donor engine for injection and accessories on engine ..... but what harness to get for front and rear brakes and lights so on.

Thx

[_Ogre]

there are 2 rubber plugs in the inner fenders and 2 rubber plugs in the core support to unplug the headlights and front turn signals
the plugs may look like a grommet, the engine harness unplugs from the engine side
then you remove the headlight wiring harness socket like a grommet, a little wd40 helps to loosen 50 yrs of crud
not a good pic but the plug is behind the top hose elbow to my ac dryer

the headlight wiring harness and socket will then come out with the headlight buckets, same for the front turn signal harness
i was able to remove the terminals from the plug and replace them with packard 56 crimp on ends and reuse both sides of the plug and socket

[dsraven]

if you have the donor wiring harness for the engine then you probably have the donor fuse/relay block as well.that is a good place to start if you want to rewire the truck yourself.you would have the relays for headlights, horn, electric engine fan, fuel pump, etc.

you can use the existing headlight switch to run through the dimmer switch and act as a power supply/signal wire to turn on the headlight relays for high and lo beam. don't forget to run a wire back to the high beam indicator as well.

the existing headlight switch is lots strong enough to run the front marker lights and taillights without a relay. it is easy to run wire from the switch out to the front marker lights and also to the tail lights. don't forget to wire the dash cluster and other interior lights a well at the same time. if you have a donor vehicle sitting there try to salvage the bulkhead connector that goes through the firewall. it is a really good way to get the wiring through the firewall without any leaks and sometimes they unplug easily from the engine side so it looks nice and tidy.

the brake lights and signals can also be wired as they were, from a "hot at all times" power source in your previously mentioned fuse /relay block, through a fuse to the brake light switch and from there up to the signal light switch and finally out to the rear brake/signal lights (since the brake and rear signal share the same bulb element). the front signals can be wired at the same time since you are under there anyway. they will need a fused power supply from a "hot with key on" supply and a signal flasher unit as well as a 4 way flasher unit.

the existing horn switch can be used to ground the horn relay.

the rest of the wiring of the truck would be as usual. not much left though. heater, interior light

[FAKKY]

Originally Posted by dsraven

maybe take a bunch of pics as you go along of different angles and especially little brackets and parts that fit together for support etc. these can be a huge asset later when you assemble the truck.

Thanks DS ... have been as I start

Originally Posted by _Ogre

there are 2 rubber plugs in the inner fenders and 2 rubber plugs in the core support to unplug the headlights and front turn signals
the plugs may look like a grommet, the engine harness unplugs from the engine side
then you remove the headlight wiring harness socket like a grommet, a little wd40 helps to loosen 50 yrs of crud

I think the PO had routed the wiring though some sort of quick diconnect .... meanign it should have been a simple harness but the wires were joined togetehr and crimped basically making a direct connection from front headlight to all the way back to firewall. Went ahead and cut them.

Originally Posted by dsraven

if you have the donor wiring harness for the engine then you probably have the donor fuse/relay block as well.that is a good place to start if you want to rewire the truck yourself.you would have the relays for headlights, horn, electric engine fan, fuel pump, etc.

Hey DS.
Haven't picked up a donor truck. Waiting till I get the front end done before seeing what is available (either complete donor or just engine/trans). Im not sure I could easily retrofit a donor truck accessory wiring harness into my truck without a lot of time and effort ....... having never done any wiring before ...... so was leaning to a labelled/schematic aftermarket harness.

Was really thinking more like .....

http://kwikwire.com/14-circuit-with-ground-kit/

Something that has enough length and clearly labelled and grouped togetehr and protected for amp draw etc appropriately.

[dsraven]

that would probably work. labeled wires are nice if you are not too sure of yourself.
do yourself a BIG favour and also invest in a quality crimper. I have a klein tool that does only two jobs, it crimps or it cuts. I like the tool because it gives a good quality crimp and has fairly long handles compared to some, so better leverage for the same amount of force applied. it means I need a second tool to strip the wire though. the crimp section has a little nub that actually pokes into the connector to force a good crimp. some crimpers are merely 2 flats that come together and I have found that the wire can easily be pulled out of the freshly crimped connection. get a stripper that has good identification/labelling on the wire ga areas. you don't want to strip a wire with a stripper section of the wrong ga. you will strip strands of wire off without even knowing if you use a groove for a smaller size wire. that area then becomes the weak spot because the ga of wire is actually less than any other part of the circuit. some crimp pliers will cut, strip and crimp. some crimpers are ratchet versions and come in a kit with different heads that can be installed depending on the wire ga and the type of connectors used, insulated or non insulated etc. in the end you want a usefull tool that is easy to work with. if you were, say, crimping 2 wires together with a barrel style connection, it would be waaay easier to use the tool if the crimper part is on the nose of the tool. if you choose to own a single tool that will do all the wiring operations you may want to get a tool that crimps and cuts on the nose of the tool and strips inside the handles of the tool. I say this because, when stripping, the wire is usually easily accessed so putting the wire between the handle grips is easy. when crimping, in some cases, the tool is in a tight area and getting the wire inside the handles can be a bit of a pain. be aware that the crimp for an insulated crimp connector is different than the tool for a non insulated crimp connector. personally I like the non insulated crimp connectors because I get to see the quality of the crimp and I also use shrink tubing on all my connections anyway so the insulated connectors are just added bulk that I sometimes have to cut off before using the connector.insulated connectors have their place, don't get me wrong. it is always a good idea to give the newly crimped connection a decent pull to ensure the crimp is good. it goes without saying that the proper size connector must be used according to wire ga. a connector that is too big can be crimped down and may work for a bit, but there will be air space inside the connector that can hold contaminants and moisture, which will ultimately cause you problems down the road somewhere. a connector that is too small can mean that not all the wire is able to be inserted correctly. this can become a resistance in the circuit and can lead to heat build up or failure of the connection, especially if it is a push on terminal. since most stuff these days is embedded in plastic heat is a bad thing.
also, use shrink tubing to protect your connections. always get the double walled type because it has something like hot glue inside it and seals the connection better. different colors are available if you want to match wire color or give certain circuits identification.
best thing you can do is google how to properly strip and crimp a wire. there is lots to know. I have seen lots of guys strip a wire then twist the strands before inserting into the crimp connector. this can actually cause the wires to cut themselves when crimped because they lay across each other, when twisted, and so when crimped hard they tend to flatten each other out and make thin spots on the strands or can actually cut each other off inside the connector.
do a circuit at a time and you won't get out of your comfort zone as quickly. you will be done in no time.

[Coupeguy2001]

up by the voltage regulator there should be 2 plugs,
one for headlights and horn, one for turn signals if the original owner bought them
unplug those and front doghouse lifts off.