Kubota WSM STa-30, Workshop Manual

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7-S7
ST
α
-30 · ST
α
-35, WSM BI-SPEED TURN
(C) Self-diagnosis Mode
Procedure 1: Making the self-diagnosis reference settings
1. Get the front wheels in the straight-run state.
2. Turn off the main switch.
Procedure 2: Changing to the self-diagnosis mode
1. Hold down the bi-speed switch and turn on the main switch (The engine does not start). Now make sure the bi-
speed lamp lights up and goes out 0.75 second later.
2. Release the bi-speed switch. This call for the “Fine adjustment and self-diagnosis mode”.
Procedure 3: Checking the lamp light-up and operating the self-diagnosis
1. First check up the bi-speed lamp. If any setting is wrong or a component part is defective or malpositioned, the
lamp starts blinking the number of times that corresponds to a trouble spot. See the “Lamp Blinks Chart” below.
If it is necessary to start the engine for making the settings again, turn off the main switch and repeat the above
step from step 1 in procedure 1.
2. When the judgement is correct, the bi-speed lamp lights up and stays on.
Procedure 4: Exiting from the self-diagnosis mode
1. Turn off the main switch.
[Lamp Blinking Chart]
NOTE
■
• The lamp flashes at the following intervals: 1.1-second on for the tens digit, 0.4-second on for the units
digit and 0.4-second off between two on’s.
• A 1.5-second off interval is put between two different pieces of data.
(D) Bi-speed Restraint Check
The bi-speed restraint function is designed to deactivate the bi-speed control when the machine is at a halt or
running at low speed (below 0.2 km/h) or high speed (above 9.0 km/h).
The following procedures are to check the travelling speed sensor output and the controller’s bi-speed restraint
function.
Procedure 1: Changing to the bi-speed restraint check mode
1. Hold down the bi-speed switch and turn on the main switch (The engine does not start). Now make sure the bi-
speed lamp lights up and goes out 0.75 second later.
2. Release the bi-speed switch. This calls for the “Fine adjustment and self-diagnosis mode”.
3. With the machine in the above mode, start the engine. The controller monitors the potential at the alternator
terminal L and calls for the “bi-speed restraint check mode” when the engine is detected to get started. (In this
mode, the bi-speed control does not work. The bi-speed restraint, depending on the input from the travelling speed
sensor but regardless of the front wheel turning angle sensor output, is shown with the bi-speed lamp.)
Procedure 2: Checking the travelling speed sensor input
1. Drive the tractor straight in each of the following 3 conditions and look at the bi-speed indicating lamp to see if the
bi-speed restraint works accordingly. The travelling speed sensor is mounted on the 33T gear of differential gear
case.
(Reference)
Checking condition A: Tractor at stop
Checking condition B: Drive the tractor with range gear shift 1, depress the HST foot pedal halfway for forward at
engine speed around 1000 rpm
Checking condition C: Drive the tractor with range gear shift 2, depress the HST foot pedal fully for forward at
engine speed around 2000 rpm
Number of blinking (times) Defective Sensor
22 Front wheel turning angle sensor
18 Travelling speed sensor
Approximate travelling speed
with standard tire
Bi-speed indicating lamp
A 0 to 0.2 km/h (0 to 0.13 mph) Lamp off
B 0.2 to 9.0 km/h (0.13 to 5.62 mph) Lamp on
C over 9.0 km/h (over 5.62 mph) Lamp off
KiSC issued 11, 2006 A