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 that the fan should be run in reverse before fan rota- 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 switch auto- 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

The switch terminals are shown in 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	NORMAL	OTHER
POSITION	CIRCUITS	CIRCUITS

NORMAL	2 + 3	NONE

REVERSE	2 + 3	5 + 6

FORWARD	NONE	NONE

	Figure 23
1. Control console	2. Cooling fan switch

4	5	6
1	2	3

BACK OF COOLING FAN SWITCH

Figure 24

Electrical System

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Groundsmaster 4100--D

Toro 4100-D service manual Cooling Fan Switch

Models: 4100-D