MicroSquirt.com read only forum (Jan.15,2018)

After a long search on this forum and reading the page http://www.megamanual.com/ms2/spare.htm
I still have a question unanswered and was hoping for someone to help me out there

Here's my current fan control setup:



The spare circuit diagram is as:



From what I read on the forum, I would need to use one of the LED pin (Pin 16, as I need to keep the warmup LED).
My question is, can I connect the pin 16 directly to the Grey 18ga wire as shown in my first picture above
Basically, the thermoswitch would be replaced by the Microsquirt spare output control.

The microsquirt can drive a relay using one of the LED outputs. The LED outputs are what are called switched ground. So like your thermoswitch they complete the circuit from the ignition switch and the relay coil to ground.

So yes you can use the microsquirt instead of the switch. You might need to check the way the tempswitch works, with the car on but not running temporarily disconnect the tempswitch while cold and make sure the fan stays off, if it turns on you have a normally closed thermoswitch, and you will have to change the output value in megatune. If it stays off then you can check that the relay and fan are working by connecting it temporarily to ground. If this is the setup you won't need to change any settings in megatune, just set a turn on and off temperature or any other conditions.

Geoff

Thanks for the comprehensive reply

I have connected the "Pin16 ACCEL LEDcc" to the wire that use to go the thermoswitch, it works.

Using the following values:

* FIdle (PM2)
o Port PM2, FIdle enabled
o variable = coolant > threshold = 180, hysteresis = 10,
o AND
o variable = rpm > threshold = 450, hysteresis = 10, (fan will not run while cranking - you can add any second condition that works for you, of course)
o Power-on value = 0
o Trigger value = 1

Thanks for the help guys