Filter
Top Products
Groundsmaster 4500--D/4700--DPage 5 -- 26Electrical System
Glow and Main Power Relays
The glowand main power relaysare located atthe pow-
er center behind the operator seat (Fig. 34). These re-
lays are attachedto the wire harness with a four (4)wire
connector (Fig. 35).
The glow relay is used to provide current to the engine
glowplugs whenenergized bythe TEC--5002controller.
The TEC--5002 controls and monitors the operation of
the glow relay.
The main power relay is used to provide current to the
TEC controllers and most of the fuse protected circuits
(headlights, operator seat, power point and optional
electric equipment). When the ignition switch is in the
ON or START position, the main power relay is ener-
gized.
Testing
1. Park machine on a level surface, lower cutting
decks, stop engine, engage parking brake and remove
key from the ignition switch.
2. Tomake surethat machine operationdoes notoccur
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. Removecover from powercenter and locaterelay to
be tested.
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 andtest leads. Subtract thisval-
ue from from the measured value of the component you
are testing.
5. Using a multimeter, verify that coil resistance be-
tween terminals 86 and 85 is approximately 72 ohms.
6. Connectmultimeter (ohmssetting) leadstorelay ter-
minals 30 and 87. Ground terminal 86 and apply +12
VDC to terminal 85. The relay should make and break
continuity between terminals 30 and 87 as +12 VDC is
applied and removed from terminal 85.
7. Disconnect voltage and testleads from the relay ter-
minals.
8. Secure relay to mounting bracket and connect wire
harnessconnectortorelay.Installcovertopowercenter.
9. 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).
1. Lock nut
2. Main power relay
3. Glow relay
4. Start relay
5. Flange head screw
6. Mounting bracket
Figure 34
2
3
4
5
1
1
5
6
Figure 35
86 87
85 30
85 86
87
30