Fan Speed Control

Fan Speed Control - System Operation:

FAN SPEED CONTROL
Fan speed is automatically controlled according to opening angle of air mix door.

Component Parts
1) Auto amplifier
2) Fan control amplifier
3) Potentio Temperature Control (PTC)
4) In-vehicle sensor
5) Ambient temperature sensor
6) Sunload sensor
7) Sunload sensor amplifier
8) Intake sensor
9) Water temperature sensor
10) Hi relay

Fan Speed Control - System Operation:

System Operation
The auto amp. determines the proper value of base current according to air mix door opening angle. This is computed by air mix door control system, which then sends this current to fan control amp. The fan control amp. amplifies its base current and makes the blower motor run. In this way blower speed is adjusted from LO to HI. "LO" air flow volume at "FOOT" or "Bi-level" mode is different from that at "VENT" or "DEF".

Fan Speed Control Specification - Air Mix Door Opening Angle:

Fan Speed When Starting or Stopping
When the blower motor starts, the auto amp. rotates the blower motor at low speed and increases speed to obtain required air amount in 5 seconds.

Fan Speed Control Specification - Fan Speed:

When stopping blower motor, the auto amp. decreases speed to low speed in 5 seconds.
Fan speed control does not operate when starting if "HI" switch is ON.