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Old Geezer-TDG Mafia #19
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Discussion Starter #1
This is a project I took on because I am to danged cheap to pay Ford for the relays to do it, and because I still have not found the place to plug in their relay/resistor. I am using the Fog Lights as a Daytime Running Light because of ease of wiring and because I don’t use them for anything else.

First off let’s lay down some ground rules.

1. It worked for me.
2. If it don’t work for you.
3. I ain’t responsible for your burnt wires.

With that said let me assure you that this has been well though out, planned, and executed on my own truck before I would do this write up. The amps in this project are very low, I have a 1.5 amp fuse in the fuse holder only as a precaution during initial testing. The gauge of wire I used is far to heavy for the situation, 18-20 gauge is plenty big. The power for the Fog Lights is being supplied by the factory wiring circuit, you are just fooling the factory relay into energizing. As a matter of fact the smaller the wire used the easier it will be for you to stuff all of it back into the connectors. If the wire you use, or you do a sloppy job of soldering, is to big the wires will be hard to put back into the connectors. Ok, on to the list of tools and materials.

1. 10mm socket and ratchet.
2. Needle nose pliers.
3. Wire cutters.
4. A very very small screwdriver to release the pins on the wire connectors.
5. Soldering gun.

1. DPST relay (Double Pole Single Throw).
2. Four different colors of 18 gauge wire.
3. Four female spade connectors.
4. Fuse holder if desired.
5. Shrink wrap.
6. Wire ties.
7. Double sided tape.
8. Solder.

The Relay that I used was from O’Reilly’s and was less than three bucks. See picture 1. It is made by MasterPro and the number is R682, however, any DPST relay will work if it has a NO (normally open) and a NC (normally closed) side to the circuit. This relay has five tabs on it. See picture 2. Tab 85 and 86 are the coil tabs, this is where you will hook up the wires to energize the relay, one is grounded the other is from the headlight power, polarity on the tabs is unimportant. Tab 87a is the NC tab that gets the wire that goes to the yellow wire on the horseshoe connector. Tab 30 is the tab that gets the key on power wire from the orange wire on connector two. All this will be better explained as we get into the install. These relays are plentiful as they are used by many auto alarm installers, you can find them online for less than a buck and a half. I got mine from O’Reilly’s because my grandson is a manager there. By the way if you want to wire something to the NO side that is not used in this application it will come on whenever your headlights are on. If you just want your Fog Lights to come on all the time, even at night with the headlights, the process is simple. Run a key on powered wire to the yellow wire on pin 17 on the horseshoe connector and your done. However, if you would like to remain friends with all those you meet at night we need to do a little more work.

Take the relay, the four female spade connectors and prewire the relay. Use about 18 inches of wire for each tab. Connect the wire to the spade connector (I soldered then shrink wrapped mine) and put one wire on each of the tabs 30, 85, 86, and 87a (if you used different colored wires write down which color is on which tab). I then put some double sided tape on the relay for mounting it to the dash brace.

Disconnect both batteries.

Remove the fuse panel cover that is just in front of your knees when you sit in the drivers seat.

Remove the four 10mm bolts that hold the fuse panel in the dash.

Pull the fuse panel out of it nesting place, this may require a bit of work because it is kind of a tight fit and it has all the wires connected to it.

Once you have the fuse panel out you will see a horseshoe shaped pull ring on a connector on the right side of the panel. See picture 3. This is the connector that has the Fog Light Relay wire on it. It is the yellow with red/orange tracer wire that is on pin number 17. See picture 4.

Just behind this connector you will see a connector that is smaller and has four wires going to it. See Picture 5 The orange wire is a key on power source. The Red with black tracer wire is a headlight on power source.

Pull the small connector with the four wires out of the fuse panel, there is a small release tab on the back side of the connector. Use the needle nose pliers and remove the red locking tab that is in the center of the connector. Use the very very small screwdriver to release the thin metal tab on the orange wire end to remove it from the connector. This may be a bit difficult until you get the hang of it. If this is to difficult to do I think the use of scotch locks in this case would be acceptable as we are in a weather protected environment. After you have soldered the wire from the #30 tab on the relay to the orange wire push it back into the connector (this is the power for the relay wire).

Remove the red with black tracer wire from the same connector. Solder the wire that comes from the #85 tab on the relay to this wire then replace it in the connector (this is the headlight on trigger wire). Push the red locking tab back into the center of the connector. Replace the connector into the fuse panel.

Your half way done.

Remove the horseshoe connector from the fuse panel, remove the red locking tab, remove the yellow with red/orange tracer wire in position 17 from the connector. Solder the wire from tab #87a on the relay to the wire and replace it into the connector (this is the wire to power the Fog Light Relay). Replace the red lock tab into the connector then replace the connector into the fuse panel.

Ground the wire that comes from the relay tab #86.

Reinstall the fuse panel, the cover, reconnect the batteries and test the system.

You should have the Fog Lights come on as soon as the key is turned to the run position, and the Fog Lights should go off as soon as the head lights are turned on. The stock factory lighting functions just as it did when stock except for the new cheap DRL’s.

Enjoy and drive in safety.

LargeCar:Thumbup: :Thumbup: :Thumbup:


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