I hope this is the place to post this, I'm going to be putting on some axillary reverse lights. I got a set of those cheap round rubber tractor lights which I love for stuff like this, now I need help wiring them.
I want to wire them with a relay and a three way switch I guess it would be called so that I can have them on, off, or on with the reverse lights.
I am in need of basically a full wiring diagram or instructions on what to wire to where. I'm no idiot I can wire things just fine I'm just not sure where to tap into the reverse lights at and I have never done a three way switch or even a relay.
Once this is tackled I'll need help doing the same thing with driving lights hooked to the high beams.
Thanks guys.

 

Here is an example that uses the 7 pin trailer tow. Unless you installed one, I do not recall the 1990 having this from the factory ( only 65 % sure of that statement ).



Instead of the orange wire going to the 7 pin trailer tow adapter, run this directly to the battery with an inline fuse, as close to the battery as you can get it.

The switch is a SPDT on-off-on switch ( 3 way is the AC voltage name for a SPDT no center off )

The switch is connected to the parking lamp circuit, so you cannot leave the aux lamps on when you leave the truck ( unless you leave the parking lamps on ).

Same thing applies to the aux lamps to the high beams, the switch is to the parking lamps, and to the high beams, with the common to the relay.

 

I have a 4 pin trailer hookup.
KC has a wiring diagram for using a spst switch and a 5 pin relay. I'm going to try that for the reverse lights tapping into either the trailer hookup if it has reverse lights or the reverse switch on the tranny since I have a manual.
I can't see your diagram right since I'm on my phone I'll look at it later.

 

SSCULLY, your posts are much appreciated! This is what i want to do also, but have no electrical knowledge.

Where do I buy the switch and relay. What do I ask for? What gauge wire do I get? What do you suggest I do to tap into the wires?

BTW, I have a 2000 model.

 

I bought my relay from ebay, cheapest place and they were here in a couple days.
I had switches but they are cheap on ebay too.
Other than that check any automtive store or harbor freight or tractor supply.
As for tapping the wire you can use tap its but I don't like them. I prefer to cut the wire and solder in the new wire with the old.

 

russo, thanks! Any suggestions for the battery connection?

 

The relay can be any automotive relay, just watch the AMP rating on it.

I cannot recall ever seeing a 10 A relay in stores, so that should not be an issue.

eBay, Amazon, other online merchants or Napa are good sources. I stay away from Autozone for this stuff, they ususlaly have the Blazer brand relays which are the compact type relays.

20 A relay @ 12.6 V is 252 W total for all the lamps on the relay.

The wire size, if you are using automotive 105*C wire, you can use 12 or 14 AWG wire. Depends on the size of the lamps, 2 55W lamps is 110 W or ~ 8.7 A of load, 2 100 W lamps ~ 17.4 A. 14 would handle the load of both, the 2 @ 100W would work better with the 12 AWG auto wire.

If you are going to use stranded wire from Home Depot ( residential wire ) this is 90*C rated wire, and at the top end the load the wire can handle is decreased, so you would want to over size the wire to 12 AWG under both conditions ( this is 90* C THHN stranded wire, or similar ).

For the connection to the battery, you can use a fork or locking fork terminal end.


Make sure to use a good pair of crimpers with these and it is best to solder the connection after crimping ( some larger terminal ends have solder in them, most of these do not ).
Heat shrink over the plastic insulation on the terminal ( I use non insulated ones and marine heat shrink ).

Get an inline fuse holder for the connection to the battery, and have it inline as close to the battery as you can get it ( if it is the pigtail type, just put the fork on one end, and solder the other end to the wire to the relay ).


I go overboard and use the LittleFuse Mega fuse holders, they have screw terminals on them, and I attached to these. Nice big lugs and wide fuse blades for plenty of contact. Mega fuses come in all sorts of sizes, so a 20A is easy to find. Just use the same mfgr of fuse for the fuse holder with mega fuses, Littlefuse has ( had ? ) a key in the holder that other mfgr of mega fuses would not slide into it. I dremmeled this keyway out of the holder.
Bussman is another brand of fuse holders.

Tapping into the parking lamp to power the switch for the relay coil, easy free method is the t-tap


Hope this helps more than hurts

 

Freaking outstanding. Thanks for taking the time to do that! I really appreciate it.

 

Should I just shove the relay under the back bumper someplace?

 

That is the easy place to put it, up by the spare tire.

Your switch you can get up behind the tail light, and have the switch in the bed of the truck.

The orange wire above, just splice to the battery circuit on the 7 pin trailer tow adapter for power with an inline fuse, no need to go to the battery ( this is hot in run position only ).

The ground lug to the frame is up high, need to drop the spare to see it.

 

I put the relay in the space behind the drivers side tail light assembly. I thought it would be safe up there and it was until I kept having to replace the relay three different times. I finally replaced the relay with a waterproof one and no more problems. I got it from the Parts Express website. Be sure to wrap up the relay good if it's not a waterproof one or you'll be replacing it like I had to.

 

Nice DJ. Thanks again SSCULLY. Russo, didn't mean to jump in on your thread.

 

Did you mean relay above, instead of switch?

 

Thank you for asking that, it did not read correctly.

Actually more correct is the wires to the switch can be routed from by the bumper up the same route as the factory S/T/T & reverse lamps to the hole by the top of the stake bed hole, to get the switch into the bed of the truck area.

The diagram above shows on with reverse, on with the switch or center off ( that is a SPDT on-off-on switch ).

Not too sure why the member above was having problems with relays, I still have the same relay controlling my aux fuse panel on my ZG-1000 since 2002. Not too many places to hide things from the weather on a motorcycle



Those are female spade terminal ends on the relay, do not even have a relay base on it.

 

Water was getting inside the relay and causing the terminals inside the relay to rust. Replacing it with a waterproof one fixed the problem. My SPDT switch for the reverse lights is inside the cab but I did install a switch for my bedcap lights inside of the left rear bed. Just put a SPDT switch there and you'll be set.