Filter
Top Products
Groundsmaster 5900/5910Page 5 -- 52Electrical System
Main Power, Controller, Start and Cab (Groundsmaster 5910) Relays
The Groundsmaster 5900and 5910 usethree (3) identi-
cal relays to c ontrol electrical power circuits. The
Groundsmaster 5910 uses an additional relay for the
cab electrical components. The relays are attached to
the operator platform under thepower center cover (Fig.
93).
The main power relay supplies electrical power for the
Info Center Display, operator seat, power point recep-
tacle, horn, road lights, brake lights and optional electri-
cal equipment. The main power relay is energized when
the ignition switch is in the START or RUN position.
The controller relay supplies electrical input power for
the two (2) electrical controllers (TEC--5001 and
TEC--5002). The controller relay is energized when the
ignition switch is in the START or RUN position.
The start relay supplies electrical power for the engine
starter solenoid. The start relay is energized by the
TEC--5002 controller when the correct start functions
are initiated (ignition switch to RUN, traction pedal in
neutral, PTO switch OFF).
The cab relay used on the Groundsmaster 5910 sup-
plies power for cab electrical functions (air conditioning,
fan, windshield washer/wiper, cab work lights). This
relay is energized when the ignition switch is in the
START or RUN position.
Testing
1. Make sure ignition switch is OFF. Remove key from
ignition switch.
2. Remove power center cover from operator platform
to access relays.
3. Disconnect the machine wire harness connector
from the relay to be tested.
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 the measured value for the tested component.
4. Using a multimeter (ohms setting), measure coil re-
sistance between terminals 85 and 86 (Fig. 94). Resist-
ance should be between 70 and 100 ohms.
5. Verify infinite resistance (no continuity) between ter-
minals 30 and 87.
6. Connectmultimeter (ohms setting)leads to relay 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 meter leads and jumper wires from the
relay terminals. Reconnect machine wire harness con-
nector to relay.
8. Install and secure power center cover.
1. Cover attachment screw 2. Relay location
Figure 93
1
2
Figure 94
86 87
85 30
85 86
87
30