MTZ 1220.3 - Medium Defects

MTZ 1220.1/1220.3 Section D. Construction and Operation
D52
Defect
code
Defect description, possible
cause
Defect check-up method
buttons. Short circuit be-
tween the wires
or locking
of one of the remote control
buttons. In this case, the
hitch linkage begins move
up- or downwards immedi-
ately after starting the en-
gine (Fig. D -37)
for mechanical damage. Disconnect each button in
turn until the defect is eliminated. When disconnect-
ing the buttons, the engine shall be stopped. If the
defect does not disappear when the buttons are dis-
connected, it is necessary to disconnect the connec-
tor from the electronic unit and check the terminals
(10) and (12), (20) and (12) for short circuit by means
of a tester.
16 Electronic unit fault.
Stabilized supply voltage of
the control panel is below
the required level. Possibly,
short circuit in the connec-
tors of the sensors of force
and RHL p
osition due to
penetration of water into
the connectors (Fig. D -37)
Disconnect the main control panel from the common
bundle. Measure the stabilized power supply voltage
on the contacts (6) (minus) and 4 (plus) of the control
panel connector, which shall be 9.5-10 V (after turn-
ing the switch of starter and instrumentation to the
“instrumentation energized” position). In case of
miss
ing or insufficient supply voltage, it is necessary
to check the reliability of connection of the electronic
unit connector. Di
sconnect in turn the sensors of
force and RHL position.
22
Fault of the position sensor.
Breakage of the sensor
wire or the sensor is not
connected or not adjusted
(Fig. D -37)
Check:
• the reliability of connection of the electric connec-
tor to the position sensor (3) (Fig. E -35c );
•
the bundle connected to the sensor for mechanical
damage;
•
the correctness of setting the RHL eccentric, i.e. in
case of maximum lowering of the RHL, the sensor
shall be pressed to the minimum extent and vice
versa;
• the correctness of adjustment of the position sen-
sor (if the defect becomes apparent when the RHL
is in the bottom position, the sensor shall be
screwed in and it becomes apparent when the
RHL is in the top position, the sensor shall be
screwed out). The adjustment sha
ll be performed
when the RHL is in the top position.
Medium defects
23 Control panel fault. The po-
tentiometer (4) of the soil
treatment depth (Fig. D -37)
is
faulty.
Check the reliability of connection of the connectors
of the control panel and electronic
unit as well as
check the bundle for mechanical damage. Check the
output voltage according to the electric diagram.
24 Control panel fault. The po-
tentiometer (3) of the top
RHL position (Fig. D -37)
is
faulty.
Check the reliability of connection of the con
nectors
of the control panel and electronic unit as well as
check the bundle for mechanical damage. Check the
output voltage according to the electric diagram.