The Stovebolt Site Forums The Shop Area The Electrical Bay Headlight relay wiring

I'm rewiring my truck and am going to add headlight relays. I know I can get the relay pigtails and headlight pigtails, but don't really want to splice them to the wiring. I've looked around but only find them with pigtails. Can someone suggest a supplier for the empty sockets and the spade terminals?

Dennis

Most of the ones we scrounge from the junk yard just have spade terminals. Usually under the hood in a plastic box. All different amp ratings.

Thanks Evan but I'm looking for new Bosch type so I don't have to splice the pigtails. Seems easy to do but maybe it isn't. Maybe that's why I only see the sockets populated so you have to splice.

Dennis

I got most of my relays at Autozone.. but I also picked up a few that were pre-wired at an auto swap meet.

All it takes is a jeweler's screwdriver to depress the lock tab on the female terminals and remove them from the pre-wired connector block. Solder your wires to the terminals, cut off the excess pigtail, and re-insert the female connectors back into the block. I do it that way all the time when I'm installing relay-controlled circuits on my Gold Wing. If desired, you can fill the back of the connector block with black RTV to hide the solder joints.
Jerry

I'll give that a try in the morning Jerry. Sounds easy enough.

Dennis

Another way to clean up the soldered connector is to slip a piece of heat shrink tubing onto the wire, then slide it over the solder joint and shrink it before re-inserting the connector into the block.
Jerry

Just for clarification Hotrod, are you saying to cut the pigtail at the terminal and solder the new wire to the terminal with no mechanical clamping?

Dennis

I use a "Western Union" splice consisting of a tightly twisted connection immediately adjacent to the female blade terminal, and solder the connection. Then I cut off the remaining pigtail and insulate the soldered joint with shrink tubing. The connection almost disappears inside the plastic connector block. You can fill the remaining area at the back of the connector block with RTV if desired. It makes a clean-looking very low resistance connection.

http://www.electricneutron.com/wp-content/uploads/2010/09/Western-Union-splice-342x350.jpg

Jerry

Thanks HRL... I've been doing it wrong all along.. that splice makes so much sense that I can't believe I never figured it out myself.

Never knew that was a Western Union splice...learn something every day. Old Bell Telephone solid wire twisted pairs were joined like that. I just called that a "phone" splice. Makes good sense that company had a lot of experience with wire.

I remember being taught that Western Union splice back in Jr. High. And that was over 50 years ago.

Compared to a butt splice connection, that one offers a lot more wire-to-wire contact, and when it's soldered, it has virtually zero voltage drop and no way to develop a loose contact.
Jerry

Hi, just wondering if you did this project and how it turned out. Did it increase your headlight output significantly? And where did you tie in the relay?Thanks kevin

I got side tracked with family things, so not made any progress. I did try a tine screw driver made for eyeglass repair, but even it was too fat to get in there. I'm thinking of filing the round shank some on it and trying again. This is a Painless fuse box. If I were to do it again I would probably use one you could attach the wires with a screw and ring terminal or something like that so I could customize it easier.

Dennis

A well supplied auto parts store should have a tool for that on the doodad rack. I have a Lisle one like this.

One leg of a small cotter pin is ideal for releasing those lock tabs on a connector block. I use a pair of needle nose pliers to grip the cotter pin piece and push it into the slot beside the female connector. This depresses the lock tab and allows it to be withdrawn from the insulator block. Do the splice, insulate the connection, raise the tab back to its original shape, and re-insert the connector into the insulator block.

Maybe I could write a tech tip with a picture sequence? It's a lot simpler to show the procedure than it is to describe it.
Jerry

That would be probably help me and others out a lot Jerry. I'm including some pictures of what I have in case my description above is off.
Fuse Panel and wires I removed

Dennis

OK- - - -you've got a slightly different connector than the Bosch relay plugs have, but the same basic procedure applies. Once the connector is removed from the block, make a soldered Western Union splice close to the connector, insulate it with shrink tubing, and re-insert it into the plastic holder. It's usually possible to re-use the locking tabs that hold the connectors in place if you carefully reshape the tabs. It looks a lot more professional than using an ugly butt splice to attach the wire to the fuse block. Good looking work so far!
Jerry

Thanks Jerry. In my no-talent move I resorted to punching the terminal out of the fuse box by using a flat tipped punch from the front. Just couldn't get anything to fit into the tight space as mentioned above. Maybe the tool Cletis shows would work though. I'm going to check with NAPA in town but haven't been that way yet. Cletis, if you see this could you comment if what you used the tool on looks like what I have? I did call Painless and asked them but they were not helpful. Said taking them out might void my warranty. I don't really care about that anyway. I know they have to take one apart from time to time rather than tossing the whole thing.

By the way Jerry, like you signature line

Dennis