fan switch?

Discussion in 'Fox 5.0 Mustang Tech' started by flashback87, May 31, 2011.

  1. Do you know how many amps that relay is rated for?

    You are fusing the fan power wire as well right? You want to use a slow-blo type MAXI fuse for that.
  2. i don't remember how many amps the relay is rated for.

    i am not fusing the fan wire. i have a 60 amp maxi fuse for the relay to battery wire.

    how important is the one for the fan wire? what size fuse?

  3. The fuse on the battery-to-terminal-30 wire is in essence fusing the fan.

    What gauge is the load-side wire going to that relay socket? It's probably not rated for 60 amps. You might end up using that small relay as a slave to drive a large relay.
  4. the wire going to the relay socked it probably 12 guage because it is a little smaller than the 10 guage wire i have tied into it.
  5. does anyone have anymore insight to why i might be blowing the fuse in the wire from the toggle switch tot he battery?

    or should i just get a new relay?

  6. Well, you aren't blowing it now...are you?

    If its holding now, tie the fan in.

    Fan wiring should go. Battery, to fuse, to terminal 30 on the relay.

    Then, terminal 87 from the relay should go to power wire of fan. Then ground the other fan wire.

    See if it works like that
  7. i found the reciept for the relay i bought so i called napa to see if they could tell me the amp rating. they could not tell and only said they could tell it was 12 volts.

    i did some research online and it looks like it is between 30-40 amps.
  8. ok, i know i have beat this thread to death but i am hoping u guys can please help me one more time.

    i want to have a light come on when my fan is on . according to diagram above i need to wire it into the fan power wire. is this the only way to do it because i am new to electical stuff and i have never wired one wire into another that goes to a power source?

    can i use 87a on the relay or will that only light up when the fan is not on?

    if the only way to do this is wiring the light into the fan power wire can someone please explain how to do this.

    thanks for all the help with my begginer questions.
  9. 87 (not 87a) is the power from the relay to the fan (by the diagram above) so you can hook your LED + to that.

    Wiring the (+) leg of the LED into the fan relay #87 will ensure the LED is indicating the fan is ON since the LED will be only drawing current when the fan is ON. That's what you want to see on the dash when it's lit.

    All you're doing is taking an LED (preferably the number listed above from Rat Shack since it's made for 12VDC and doesn't need a resistor), soldering (preferably) a wire to the short leg (-) and a wire to the long (+) leg (LEDs have one leg longer than the other). Connect the wire from the short leg of the LED to ground (ground behind the dash, frame, whatever). Connect the wire soldered to the long leg of the LED to #87. Obviously you'll need a few feet of wire to go from the fan's relay to the location on the dash where you'll install the LED. The wire can be pretty small since it's not carrying any current. Make SURE the wire from the fan relay to the LED is wrapped, covered, heatshrunk, whatever, no bare wire or connectors touching anything. LEDs are cheap so buy more than one just in case you cook one.
  10. thanks, how do i connect the led wire to the 87 terminal?
  11. You could put it inside the connector for the 87 wire before you solder the wiring connector. It could also be done at the fan-motor end when doing the freewheeling diode.
  12. thanks,

    ok, i am sure this is common knowledge but i have never done this. lets say i do the diode way. from the diagram above it looks the the diode and the led power wire are merged into the 10 guage fan wire. how would i merge all three of those wires?

    that is what i am trying to figure out.

    also, is the diode neccessary?

    thanks again, you guys are really educating me
  13. They sell wire taps for 10g wire that you crimp over the wore


    Radio shack has these. They are two parts. One part crimps over the wore, the other part you crimp on the wire you want to connect. Then press them together.


    I use these for non critical connections or where I can't solder. They hold up well.

    Whole setup will look like this

  14. There is also an alternate style wore tap

  15. And I'd already mentioned that you could merge them in the electrical connector itself. That's simpler, and in my experience, taps don't like heat or vibration for extended periods of time.

    The diode is not critical but it helps maximize relay life.
  16. Right. Don't over complicate it flashback :) you could even peel back some of the insulation along that 10 gauge and solder it in anywhere. Just wrap it back up good with some heat shrink or cold shrink. You'll do fine :flag:
  17. sweet, thanks for all the replies and help
  18. ok, so im back on this. i might have found my answer on another forum but i wanted to double check with your guys because i respect your advice:SNSign:

    i got a 75 amp relay and a new toggle switch. i verified it is hooked up right and re connected all my grounds. i also put in a green led light, really good idea thanks:nice:. now the fan will work for 2-3 cruises and the fuse in the fuse hold from relay to battery will blow. i have a 30 amp fuse in right now. i read on another forum that some people are using 40 amp or 60 amp. i have a mega fuse holder with a 40 and 60 amp fuse. is the 30 amp too weak and should i be using one of the maxis fuses?

    also, does anyone have the taurus fan only hooked up on low? my car came with a conical filter and just recently i found a car with the air box. so i took my conical filter off and put in the stock air box. car is running cooler now, idles better and just performs better:shrug: so i was wondering if i could just run it on the low speed and still keep my car cool. on high my car does not go over 198.

    i know this thread is long and i really hope some takes the time to answer this:D

    thanks a lot
  19. The sn95 uses a similar fan. In fact the motor is interchangeable. It uses a 60A maxi-fuse.

    The maxi-fuse is a slow-blow type. That way the initial spike on fan start up won't blow it. If you go to auto zone you can find these fuses for sale. A stereo shop might have a maxi-fuse holder, or you can get one online

    If low speed keeps your car cool enough, go for it. Less current draw and parasitic loss through the alternator. With an efficient cooling system, you really only need the fan at idle. Mine comes on for a few seconds when idling, but during normal cruising it's pretty much off
  20. Thanks mustang5l5, im gonna throw the maxi fuse back in