Functional Checks; Distinguishing Between Electrical And Hydraulic Malfunctions; Checking The Electrical Operations; Checking The Lift/Lower Switch - Valtra 6000 Workshop Manual

32. Electro---hydraulic power lift
1

Functional checks

If a malfunction should occur, the reasons may be either in the
electric control system or in the hydraulic system:
1. Distinguishing between electrical and
hydraulic malfunctions
--- Start the tractor. Apply the parking brake.
--- Press the push buttons at the ends of the solenoids on the
control valve. This moves the valve plunger mechanically. The
lifting solenoid is the most accessible
--- If the lower links move upwards and downwards, the hy-
draulic circuit is in order
--- If the lower links fail to move when the buttons are de-
pressed, check the condition of the pump and oil pipes. If
necessary, the control valve must be checked (see section
90).

2. Checking the electrical operations

Important! The most likely causes of malfunction are poor
contacts in the connectors and switches. In case of malfunc-
tion, all connectors and switches must be checked and
cleaned. Most of the connectors are placed in the lever con-
sole. Connectors for sensors are at the rear of the tractor on
right side.
A. Checking rear push buttons
--- Start the tractor
--- Set the lift/lower switch (2) in the lowering position
--- Press the buttons on the mudguards and check if the lower
links actually move upwards and downwards:
a) If the lower links respond to the push buttons, then this sec-
tion is in working order
b) If the lower links do not move when the buttons are
pressed:
--- check the power lift fuses (F11 5 A, F18 5 A)
--- check the constant current (X2E/1) and current passing
through the ignition switch (X2E/3) from the power lift inlet
connection (X2E)
--- check the lead connections for breaks and repair if necess-
ary
8. 11. 1990
2
c) If the lower links e.g. lift but will not lower:
--- Change round wires to the solenoids and try the buttons
again:
--- If the lower links still move upwards only, the lower solenoid
is defective and must be changed
--- If the lower links move downwards only, the valve is in order,
but the other solenoid is not receiving current. In this case,
check the lead connectors.
B. Checking the lift/lower switch
The power lift control system is activated with this switch. (2).
If the unit is not receiving current or information about the posi-
tion of the lower links (e.g. the position sensor lead is dam-
aged), the control system will not start to function and the
power lift will not respond to the position control knob (1)
If the control system does not start to function, but the lower
links respond to the push buttons:
--- Check the lift/lower switch and the associated connections
(if the power lift is left unused for some time the switch may
become oxidized, and the control system will fail to activate).
--- Check the position sensor lead and the other connections
--- Check the electronic unit connection
If no defect is found, the whole electronic unit must be re-
placed. The unit is fitted to the lever console on the cabin.
C. Checking the position control knob (1)
--- Activate the control system (switch 2)
--- Turn switch (4) to position 9.
--- Rotate the position control knob slowly to its extreme posi-
tions. The movement of the lower links should be steady
(clockwise extreme position=max transport height. Anti ---
clockwise extreme position=lowest position of lower links.
Note! The numbers beside the position control knob and the
transport height selector correspond to each others
Note! Checking the position control knob, see page 320/14.
294
Model
6000-- 8400
15. 6. 1992
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4
6
7
Code Page
320 8
5
8