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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Need help wiring electric fan

  • Thread starter Thread starter johnny_261
  • Start date Start date Dec 30, 2010
J

johnny_261

Member
Dec 10, 2006
42
0
6
Dec 30, 2010
#1
  • Dec 30, 2010
  • #1
Hi Everyone,

I bought a used black magic fan for my car and I'm in the process of wiring it up. It came with a controller unit that has a built in relay. I want to wire this to the ignition circuit so that the fan will turn on only when the ignition is on. The controller unit has already been mounted to the fan shroud on the passenger side and I'm wondering where the easiest place is to tap into the ignition circuit. I obviously would like to minimize the amount of wiring that I run.

Thanks for your help!
 

jrichker

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Dec 30, 2010
#2
  • Dec 30, 2010
  • #2
If you don't have a high current alternator, you can forget about using the fan. The stock 65 amp alternator isn't big enough to run the fan and the rest of the car.

The low coolant sensor has a wire that is hot when the ignition switch is on. The ignition coil has a red/lt green wire that is hot when the ignition is on as well.

Diagram courtesy of Tmoss & Stang&2birds



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring Mustang FAQ - Wiring & Engine Info Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

Electric fan = 3G alternator if you want long life & reliability from your car.
The electric fan saves some HP. The stock fan's parasitic drag runs from 7-12 HP depending on who you talk to. The electric fan uses about 1/2 HP of power from the electrical system.

Figure this:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
Fan (heater or A/C) = 15 amps (can run between 5-25 amps depending on setting)
Radio & instruments = 10 amps
Wipers = 10 amps

That's grand total of 74 amps from a 65 amp alternator. Talk about overdrawn at the bank!

Stangnet 3G install sticky http://forums.stangnet.com/showthread.php?t=646825
 

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
Dec 30, 2010
#3
  • Dec 30, 2010
  • #3
http://static.summitracing.com/global/images/instructions/flx-175.pdf
 
J

johnny_261

Member
Dec 10, 2006
42
0
6
Dec 30, 2010
#4
  • Dec 30, 2010
  • #4
Hey that's great. Thanks for the help and the links.

I just finished installing my 3g alternator last night, so that's why I'm moving on to the electric fan. With your help, installing the fan should be snap now.
 

4rdnut

Member
Dec 14, 2010
188
1
16
Dec 31, 2010
#5
  • Dec 31, 2010
  • #5
The controller that comes with that fan is garbage, get the variable speed controller from flexalite, i know, i bought a new black magic extreme #185 fan for my mustang. The controller that came with my fan had a loose circuit board and would turn the fan on and off at all different temps on its own, get the "vsc" controller. I complained to flexalite and they gave me the variable speed controller for free. The flexalite fan motor itself is a great product, its made in canada. The black magic controller, made in china. I would also solder every wire and connection, if you dont, you will regret it later down the road.
 
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