Toro Groundmaster Series Service Manual page 235

Testing Relays with 4 Terminals
Groundsmaster ® 3200, 3300 and 3310
19240SL Rev A
•
The main power relay supplies power to the fuses (and all of the circuits
protected by the fuses) in fuse block 2; refer to
Function (page 6–12). The main power relay is energized when the key
switch is in the R
UN
•
The glow plug relay supplies power to the engine glow plugs. For model
31900 and 31901 machines; the glow plug relay is energized while the glow
switch is pressed. For model 31902 and 31903 machines, the glow relay is
energized by the Yanmar engine ECU.
•
The pull coil relay supplies power to the pull coil of the engine fuel solenoid
(models 31900 and 31901 only). The pull coil relay is energized by the start
interlock relay and the delay timer.
•
The cab power relay supplies power to the cab control circuits of
Groundsmaster 3310 machines.
•
The horn relay supplies power to the optional horn.
Refer to Figure 93 for this procedure.
1. Park the machine on a level surface, lower the cutting unit (or attachment),
engage the parking brake, set the key switch to the O
the key from the key switch.
2. Disconnect the ground cable at the battery; refer to
the Battery (page 6–64).
3. Remove the operator's console covers; refer to
Operator's Console Covers (page
4. Locate the relay that is to be tested and disconnect the wire harness
connectors from the relay. Check the relay and the harness connector for
damage or corrosion and clean or repair if necessary.
g256779
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 value from the measured value for
the tested component.
5. Using a multimeter (ohms setting), measure coil resistance between
terminals 85 and 86. Resistance should be between 70 and 100 ohms.
or S position.
TART
7–23).
Figure 95
Relay with 4 terminals
Page 6–43 Electrical System: Testing the Electrical Components
Fuse Identification and
position and remove
FF
Removing and Installing
Removing and Installing the