Service Manual

Workman HDX Page 3 − 5 Kubota EFI Gasoline Engine
Kubota Gasoline Engine Electronic Control Unit (ECU)
The Kubota gasoline engine that powers your Workman
HDX uses an electronic control unit (ECU) for engine
management. All wire harness electrical connectors
should be plugged into the ECU before the machine igni-
tion 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) and software, and the Kubota Diagnostic
Manual should be used to provide assistance in identify-
ing the cause of the problem and any repairs that are ne-
cessary. Connect the Kubota Gasoline Service Tool
(KGST) to the diagnostic connector above the engine
ECU (Fig. 3). Contact your Toro distributor for assist-
ance in Kubota engine troubleshooting.
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.
Figure 2
1. Engine (Model 30809)
2. Engine ECU
1
2
Figure 3
Diagnostic connector
Kubuta EFI
Gasoline Engine