94-95 Mustangs Cooling Fans
From Mustang-Tech
Contents |
Fan On/Off Settings
The stock temperature gauge is notoriously inaccurate - 200 degrees may be on the "O" in NORMAL for one person while it may be on the "A" for others.
The ECT sensor, located in the front passenger side of the lower intake, sends the temperature of coolant to the EEC and controls various fuel and spark modifications as well as the fans.
Automatic/Manual GTs
- Highspeed fan cuton/off is at 228/220
- Lowspeed fan cuton/off is at 208/204
Cobras
- Highspeed fan cuton/off is at 228/220
- Lowspeed fan cuton/off is at 216/212
Fan Switch
Wiring up a low-speed fan switch
Perform wiring modifications at your own risk.
You will choose your switch location. Popular locations are the shifter bezel or the ashtray (creating or purchasing a switch panel from the aftermarket).
You will source accessory 12 volt power. The donor circuit rating is not of paramount importance because the relay coil you will energize draws less than 0.5 amps. Some choose to use the harness for the convertible-top switch (as is popular with the fog-light rewire) but most any decent-sized circuit near your switch should work. Connect a wire to this source and run the wire to the power terminal on your switch. It is a wise idea to fuse this wire; a two or three amp fuse should be more than sufficient.
You will run a wire from the ‘accessory’ terminal of your switch to CCRM Pin 14 (often a dark blue wire). You will tap into this wire (like a Y or Tee connection. Do NOT cut the wire).
If you have a lighted switch, find a clean chassis ground and run a wire from this ground to the ground or illumination terminal on your switch. Just ensure that you do not inadvertently connect ground to the power or accessory terminals of your switch.
What is occurring is that when you flip the switch, 12 volts is sent to the low speed fan relay’s coil, which energizes the relay. The load-side of the circuit is still sourced as it is in OEM form (battery to fan-relay, fan-relay to fan). The OEM fan triggering also still functions.
- See the note below regarding cautions with the use of fan switches
Wiring a High-speed fan switch
Perform wiring modifications at your own risk.
Choose your switch-mounting location as noted above.
For this switch, you will be sourcing ground and sending it to the high-speed fan relay’s coil. Connect a wire to ground. Run this to the power terminal of your switch.
Run a wire from the accessory position of the switch to CCRM Pin 17 (it is often green with a purple tracer).
That’s all there is to this.
- See the note below regarding cautions with the use of fan switches
A note or two about installing a low-speed switch, high-speed switch, or both
Be cognizant of your fan switch positions and the OEM fan control. You do not want to have both fan speeds running simultaneously, as this shortens the fan-motor life, draws excessive current, and causes the fan to run slower than it would on high-speed alone. If someone desires to run high-speed and the fan is not already running, it is best to run low-speed first and once it’s up to speed, turn off low-speed and engage high-speed. This lessens the shock on the electrical system and limit’s the duration of the start-up draw through the high speed fan terminal (a problem area on 94-95 two-speed fans).
If questions or comments arise, check your wiring schematics, favorite forum or contact HISSIN50.
