Troubleshooting; Verify Diagnostic Display Input Functions - Toro Groundsmaster 4700-D Service Manual

Troubleshooting

CAUTION
Remove all jewelry, especially rings and
watches, before doing any electrical trouble-
shooting or testing. Disconnect the battery
cables unless the test requires battery voltage.
Diagnostic Display
Groundsmaster 4500--D and 4700--D machines are
equipped with one (GM 4500--D) or two (GM 4700--D)
Toro Electronic Controllers (TEC) which control ma-
chine electrical functions. The controllers monitor vari-
ous input switches (e.g. ignition switch, seat switch,
neutral switch) and energize outputs to actuate sole-
noids or relays for the requested machine function.
For the TEC to control the machine as desired, each of
the inputs (switches and sensors) and outputs (sole-
noids and relays) must be connected and functioning
properly.
The Diagnostic Display (see Special Tools in this chap-
ter) is a tool to help the technician verify correct electrical
functions of the machine.
IMPORTANT: The Diagnostic Display must not be
left connected to the machine. It is not designed to
withstand the environment of the machine's every
day use. When use of the Diagnostic Display is com-
pleted, disconnect it from the machine and recon-
nect loopback connector to harness connector. The
machine will not operate without the loopback con-
nector installed on the harness. Store the Diagnos-
tic Display in a dry, secure, indoor location and not
on machine.
CAUTION
The interlock switches are for the protection of
the operator and bystanders and to ensure cor-
rect operation of the machine. Do not bypass or
disconnect switches. Check the operation of the
interlock switches daily for proper operation. Re-
place any malfunctioning switches before oper-
ating the machine.
Electrical System
For effective troubleshooting and repairs, there must be
a good understanding of the electrical circuits and com-
ponents used on this machine (see Chapter 9 -- Electri-
cal Diagrams).
If the machine has any interlock switches by--passed,
reconnect the switches for proper safety and trouble-
shooting.
NOTE: Use the Diagnostic Display (see Special Tools
in this chapter) to test Electronic Control Module inputs
and outputs when troubleshooting an electrical problem
on your Groundsmaster.

Verify Diagnostic Display Input Functions

1. Park machine on a level surface, lower the cutting
decks, stop the engine and apply the parking brake.
2. Remove plate in front of seat to allow access to wire
harness loop back connector. Locate wire harness and
loop back connector (Fig. 8). Carefully unplug loop back
connector from harness connector.
3. Connect the Diagnostic Display connector to the
wire harness connector. Make sure correct overlay de-
cal is positioned on the Diagnostic Display (Figs. 9 and
10).
4. Turn the ignition switch to the ON position, but do not
start machine.
NOTE: The red text on the Diagnostic Display overlay
decal refers to input switches and the green text refers
to TEC outputs.
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1. Wire harness connector
2. Loop back connector
Page 5 - - 6
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Figure 8
3. Diagnostic display
Groundsmaster 4500--D/4700--D
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