Toro 07390 Workman HDX-Auto, Service Manual

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Workman HDX Auto Page 6 − 20 Electrical System
Relays with Five (5) Terminals
Workman HDX Auto vehicles use a number of relays
that have five (5) terminals:
The start relay ensures that the hydraulic lift lever is in
neutral before the engine starter solenoid can be ener-
gized. The start relay also prevents starting if the high
flow hydraulics system (if equipped) is engaged.
The fan relay allows powers to the engine cooling fan
when the relay is energized.
The start enable relay ensures that the brake pedal is de-
pressed before the engine starter motor can be en-
gaged.
The rear differential relay is used to make sure that the
rear differential solenoid is not energized when the park-
ing brake is applied or if the transmission is in the neutral
or park position. This will ensure that the rear wheels are
locked when the vehicle is parked.
The front differential relay on vehicles equipped with
4WD is used to disengage the front wheel drive differen-
tial solenoid. If the front differential interrupter switch is
pressed or the transmission is in the neutral or park posi-
tion, the front differential relay will be de − energized to
ensure that front wheel drive is disengaged.
The start and fan relays are attached to the relay bracket
under the right side of the bed near the engine (Fig. 25).
The other relays are located behind the dash panel
(Fig. 26).
Testing
1. Park machine on a level surface and apply parking
brake.
2. If relay is located on relay bracket (Fig. 25), raise bed
and install bed support on bed lift cylinder to prevent bed
from lowering. Stop engine and remove key from ignition
switch.
3. If relay is located behind the dash panel (Fig. 26), re-
move hood to access relay (see Hood in the Service and
Repairs section of Chapter 5 − Chassis).
4. Locate relay that is to be tested and disconnect the
wire harness connector from the relay. Remove relay
from machine for easier testing.
NOTE: Prior to taking small resistance readings with a
digital multimeter, short the meter test leads together.
The meter will display a small resistance value (usually
0.5 ohms or less). This resistance is due to the internal
resistance of the meter and test leads. Subtract this val-
ue from from the measured value of the component you
are testing.
1. Start relay
2. Fan relay
3. Screw (2)
4. Relay bracket
Figure 25
1
2
3
FRONT
4
1. Start enable relay
2. Rear differential relay
3. Front differential relay
4. Screw
Figure 26
FRONT
1
2
3
4