Start And Air Conditioning (Groundsmaster 4110--D) Relays - Toro Groundsmaster 4100-D Service Manual

Start and Air Conditioning (Groundsmaster 4110- -D) Relays
When energized by the TEC--5002 controller, the start
relay is used to provide current to the engine starter mo-
tor solenoid. The TEC--5002 controls and monitors the
operation of the start relay. The start relay is located at
the power center behind the operator seat (Fig. 36).
An identical relay is used to control the air conditioning
electrical power circuit on the Groundsmaster 4110--D.
When energized by the air conditioning switch, the relay
provides current for the air conditioning components.
The relay is attached to the evaporator assembly in the
cab headliner.
Testing
1. Park machine on a level surface, lower cutting deck,
stop engine, engage parking brake and remove key
from the ignition switch. Raise and support hood.
2. To make sure that machine operation does not occur
unexpectedly, disconnect negative (--) cable from bat-
tery and then disconnect positive (+) cable from battery
(see Battery Service in the Service and Repairs section
of this chapter).
3. Remove cover (item 1) and heat shield (item 9) from
power center and locate relay to be tested. If necessary,
remove two (2) flange nuts and carriage screws that se-
cure power center to tank support.
4. Disconnect wire harness connector from relay. Re-
move relay from mounting bracket for 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.
5. Using a multimeter, verify that coil resistance be-
tween terminals 85 and 86 is from 71 to 88 ohms.
6. Connect multimeter (ohms setting) leads to relay ter-
minals 30 and 87. Ground terminal 86 and apply +12
VDC to terminal 85. The relay terminals 30 and 87
should have continuity as +12 VDC is applied to terminal
85. The relay terminals 30 and 87 should not have conti-
nuity as +12 VDC is removed from terminal 85.
7. Disconnect voltage from terminal 85 and multimeter
lead from terminal 87.
8. Connect multimeter (ohms setting) leads to relay ter-
minals 30 and 87A. With terminal 86 grounded, apply
+12 VDC to terminal 85. The relay terminals 30 and 87A
should not have continuity as +12 VDC is applied to ter-
Groundsmaster 4100--D/4110--D
minal 85. The relay terminals 30 and 87A should have
continuity as +12 VDC is removed from terminal 85.
9. Disconnect voltage and multimeter test leads from
the relay terminals. Replace relay if necessary.
10.Secure relay to mounting bracket and connect wire
harness connector to relay. Secure power center to tank
support if it was removed. Install cover (item 1) and heat
shield (item 9) to power center.
11. Connect positive (+) cable to battery and then con-
nect negative (--) cable to battery (see Battery Service
in the Service and Repairs section of this chapter).
12.Lower and secure hood.
3
2
6
RIGHT
FRONT
1. Cover
2. Screw
3. Flange nut (2 used)
4. Carriage screw (2 used)
5. Screw
1. Coil terminal
2. Common terminal
Page 5 - - 31
1
10
9
8
7
4
Figure 36
6. Mount
7. Lock nut
8. Start relay
9. Heat shield
10. Screw (2 used)
3
1
86 87A 87
85 30
1
Figure 37
3. Normally closed term.
4. Normally open term.
Electrical System
5
4
2