Toro Groundsmaster 3500 30807 Service Manual page 43

Kubota Gasoline Engine Electronic Control Unit (ECU)
The Kubota gasoline engine that powers your Ground-
smaster 3500−G uses an electronic control unit (ECU)
for engine management. All wire harness electrical con-
nectors should be plugged into the ECU before the ma-
chine ignition switch is moved from the OFF position to
either the ON or START position.
The engine electrical components (e.g. ECU, O2
sensor, throttle control, power relay, ETV relay) are iden-
tified and matched in the engine ECU program. If engine
electrical components are replaced on the engine, the
Kubota electronic tool must be used to update the ECU
program which will ensure correct engine operation.
If the engine ECU identifies that an engine problem ex-
ists, the check engine light on the Operator's Control
Panel will illuminate. The engine speed may be reduced
or the engine might stop. The Kubota Gasoline Service
Tool (KGST) software, the Ecom interface driver and
diagnostic cable, and the Kubota Diagnostic Manual
should be used to provide assistance in identifying the
cause of the problem and any repairs that are neces-
sary. Use the diagnostic cable to connect a PC running
the KGST software and Ecom interface driver to the dia-
gnostic connector above the engine ECU (Fig. 3). Con-
tact your Toro distributor for assistance in Kubota engine
troubleshooting, or to acquire Kubota engine software
and hardware.
IMPORTANT: Two (2) communication connectors
are located near the engine ECU. The connector
along side of the ECU (near the middle of the engine)
is not used for service diagnostics.
Do not plug or unplug the engine ECU for a period
of thirty (30) seconds after the machine key switch
is turned OFF. The ECU may remain energized even
though the ignition switch is OFF.
If the engine ECU is to be disconnected for any reason,
make sure that the ignition switch is in the OFF position
with the key removed before disconnecting the engine
ECU. Also, to prevent possible ECU damage when
welding on the machine, disconnect and remove the en-
gine ECU from the machine before welding.
Groundsmaster 3500−G
1
1. Engine (Model 30809)
2. Engine ECU
Page 4 − 5
Figure 2
Figure 3
Diagnostic connector
Kubota Gasoline Engine
2