Micro Autonomations LLC – Fan Controller v3
6
Document Rev 1.0
Note:
Use this input only if there are no other EFI/gauge connections to the temperature sensor. Connecting
this input to an EFI/gauge signal could change the temperature reported to the EFI system, causing
significant issues.
Standalone Temperature Sensor Return (GND) – White - 9
This pin is internally connected to ground. When using a two terminal temperature sensor, connect one
terminal to this pin. Leave this pin unused when using a single terminal temperature sensor.
EFI Temperature Sensor – Purple - 5
This input may be connected to a temperature sensor connected to an EFI computer system. Its input
range is 0v-5v. Some aftermarket temperature gauges may use a 0-12v signal – verify this before
splicing this wire into the temperature sensor wire. Both positive or negative going sensors may be used
with the controller.
Note:
Use this input if you are piggybacking on the temperature sensor used by MegaSquirt, or any other EFI
system, even if it uses the standard GM sensor
Remote Status LED – Gray - 10
This output may drive the included LED which can be mounted remotely within view of the driver. The
LED is dual color, but only one color may be chosen during installation. Install the Red wire from the LED
to this pin for a Red color, and the other wire to ground. Or, reverse the colors for a Green status light.
The LED requires a ¼” hole to mount in, and has 6” long tinned wires.
The controller is designed to drive an LED with a forward voltage of 2v-2.2v, while supplying 12mA. Any
other suitable LED may be used if desired to match existing indicator lights on the dash. Contact me to
verify that your LED will work if you have any questions.
Mode
Action
Vehicle start
After doing a self-check, if no errors found, the Remote Status LED will be solid for 5 seconds
Fan turns On
When the fan turns on, the Remote Status LED will be solid for 5 seconds, then blink
once
Fan turns Off
When the fan turns off, the Remote Status LED will be solid for 5 seconds, then blink
twice
Air Cond. is
activated
When the fan is activated by the air conditioning signal, the Remote Status LED will be solid
for 5 seconds, then blink
three times
Error
If there is an error, the Remote Status LED will blink in a pattern of 2, 3, or 4 blinks. See the
‘Error Mode’ section for explanation of each code.
Fan at full
speed
If the temperature requires the fan to operate at full speed, the Remote Status LED will turn
on steady until the fan speed drops below full speed
