Toro 4100-D Lawn Mower User Manual


 
Groundsmaster 4100--DPage 5 -- 16Electrical System
Cooling Fan Switch
The cooling fan switch is used to control the operation
of the hydraulic cooling fan and is located on the control
console (Fig. 23). This switch has three (3) positions:
Reverse, Auto and Forward.
When the cooling fan switch is in the normal Auto posi-
tion, cooling fan operation is controlled by the
TEC--5002 controller. In this switch position, if either en-
gine coolant or hydraulic oil temperature is excessive,
the fan will stop and then reverse direction to allow auto-
matic debris cleaning of the radiator, oil cooler and rear
intake screen. The controller determines the length of
time thatthe fan should berunin reverse before fanrota-
tion is returned to the forward direction.
If the operator depresses the cooling fan switch to the
Reverse position, a fan reverse cycle that is controlled
by the TEC--5002 controller is initiated.The switchauto-
matically returns to the Auto position and fan operation
returns to the forward direction after the reverse cycle is
completed.
If the cooling fan switch is placed in the Forward posi-
tion, the engine cooling fan will run only in the forward
direction.
Testing
Theswitchterminals areshownin Figure 24.The circuit-
ry of the switch is shown in the chart below. With the use
of a multimeter (ohms setting), the switch functions may
be tested to determine whether continuity exists be-
tween the various terminals for each position. Verify
continuity between switch terminals.
SWITCH
POSITION
NORMAL
CIRCUITS
OTHER
CIRCUITS
NORMAL 2+3 NONE
REVERSE 2+3 5+6
FORWARD NONE NONE
1. Control console 2. Cooling fan switch
Figure 23
1
2
Figure 24
BACK OF COOLING FAN SWITCH
132
456