how to install fog lights on 620

[sick620]

how do i install fog lights on my 79 620. my fog lights are just simple old school fogs with a single wire coming from each with a little metal tip on each..... where do i wire these to and how do i do it? any takers?:o

[OG lil E]

It's not too hard of a project, but it will take some time. You will need to buy a few things. First thing you need to buy is a 5 prong Bosch style relay. You can buy these just about anywhere. You will also need some kind of switch, some wire and wiring terminals.

 

First of all, disconnect your battery. Working with it hooked up can be disasterous. Don't take any chances.

 

You need to mount the lights to something metal. Since they only have a single wire coming out of them, they need to be mounted on metal so they will ground.

 

The next thing you need to do is mount the relay. Usually you can mount it on the firewall. If you don't mind drilling a few holes, you can mount it under your dash if you like. At this time you will need to find an existing hole in the firewall to run wires through from the relay, battery, etc. If you can't find an existing hole, you will have to drill one. Make sure BEFORE you drill that there is nothing you're going to drill through on the other side like the heater core, wires, cables, etc. Also, after you drill the hole, make sure you use a rubber grommet to insulate the hole. The rough edges of the hole can cause the insulation of the wire to get stripped and expose the wire itself and cause a short or possibly a fire. Take your time and do it right.

 

Next, you will need to mount a switch of some sort in or under your dash. Drill the necessary hole to mount it and make sure it is away from any moving stuff like your pedals, but don't mount it yet. It makes it easier to wire if it isn't completely installed yet.

 

After you mount the relay, you need to wire it up. There are 5 terminals on the relay you will be using. They are numbered 30, 85, 86, 87 and 87a. Each terminal needs to be wired up as follows:

 

85--goes to ground. Get a short wire and go from the relay to a good metal surface under a screw or bolt. You can also put it under the screw that holds the relay, but you have to make sure it has a good ground.

 

30--Fused power from battery. Get an inline fuse and hook it up to the positive side of the battery. Make sure you don't install the fuse yet. Get a length of wire and run it from the end of the fuse wire and hook it up to the relay terminal 30.

 

87 & 87a---Add a length of wire to each of the fog lights and run it up to the relay---one wire for each light. Hook up one light to terminal 87, and the other to 87a.

 

86--Hook a length of wire to the relay terminal 86 and run it back through the hole in the firewall and put it on the appropiate terminal on the switch. Depending on what kind of switch you use will determine which terminal this wire goes to. I'll assume you'll buy a lighted toggle type switch available at Wal-Mart, Auto-Zone or Checker Auto. These type of switches have 3 terminals. They will be labelled power, accessory and ground. Hook up the wire from terminal 86 on the relay to the "accessory" terminal on the switch.

 

Next, take another small length of wire and run it from the terminal on the back of the switch marked "ground" to under a self tapping screw or bolt. This is the ground wire for the illumination on the switch.

 

Now, you need to decide where you want the power to come from for the switch. Get another length of wire and hook it up to the switch. This wire goes from the terminal on the switch marked power. Take the other end of the wire and hook it to a terminal on the fuseblock labelled "accessory". You will need some kind of wire tap, or you can take the fuse out of the terminal and carefully wrap the wire around it and re-install the fuse. Your 620 will have glass fuses, so wrapping the wire can be tricky. Also, Datsun fuse panels like so many older Japanese cars have a tendency to get hot. It might not be a bad idea just to run the power wire all the way out to the positive side of your battery. If you do, make sure you use a fuseable link for that (just like you did for the relay). Also, you have to be sure you don't forget to turn the fog lights off when you get out of your truck at night. They will stay on after you turn off the truck.

 

After all the wires are hooked up, you can install the switch.

 

Next you need to install fuses in the fuseable links. I'd recommend 15 or 20 amp fuses for each of the fuseable links you installed. One for the relay and one for the fog lights. After the fuses are in, hook up your battery and test the lights. You might want to make sure the truck is running. Factory Datsun alternators only have about 30 amps of output, and stuff like fog lights and stereo can really pull the power.

 

Well, I think that's about all. It really isn't that hard, it just takes time to do a safe and neat install. Good luck! E

[sick620]

that is very helpful thanks for taking your time to write that bad boy that was a novel. is that the only way to do it using a toggle like that. would it be possible to do it straight to the running lights or anything? it wuld b cooler wit a toggle huh

[Loz]

a separate switch won't overload your existing wiring loom. Safe and smart.

[Bleach]

Or power it by a relay off the battery. You can have the relay turn on and off by getting its signal from a running light if you wish. That will keep the main current off your original circuit.

[sick620]

bleach i kinda like your idea but i'll figure it out soon and get pics of my truck up