Main Power And Glow Relays - Toro Workman MDX-D Service Manual

Main Power and Glow Relays

The Workman MDX--D main and glow relays are at-
tached to the front of the dash bracket and can be ac-
cessed by raising the hood (Fig. 17). The vehicle wire
harness is attached to the main and glow relays with four
(4) wire connectors. Relays can be identified by a tag on
the wire harness.
The main power relay is used to provide current to the
fuse blocks. When the ignition switch is in the ON or
START position, the main power relay is energized.
The glow relay is used to provide current to the engine
glow plugs when the relay is energized by the glow plug
controller.
Testing
1. Park vehicle on a level surface, stop engine, apply
parking brake and remove key from ignition switch.
Open and support hood to access relays.
2. Make sure ignition switch is in the OFF position. Dis-
connect wire harness electrical connector from relay
that is to be tested. Remove relay from dash bracket 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 the measured value of the relay being testing.
3. Verify coil resistance between terminals 85 and 86
with a multimeter (ohms setting). Resistance should be
approximately 72 ohms.
4. Connect multimeter (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.
5. Disconnect voltage and leads from the relay termi-
nals. Replace relay if testing determines that it is faulty.
6. Secure relay to dash bracket and connect wire har-
ness electrical connector to relay after testing is com-
pleted.
7. Close and secure hood.
Electrical System
2
1. Main power relay
Page 5 - - 14
1
Figure 17
2. Glow relay
85
87
86 87
85 30
Figure 18
Workman MDX--D
30
86