Troubleshooting - Haier HT1206TXVE Service Manual

Possible Possible
S/N
Malfunctions causes
Transportati
Time
on part of
remains the
the 5 cable
same after
connectors
revolving the
(ST4-1~ST-5)
on the
1 knob; or
program
remains the
selecting
same on part
board is all
programs
or partly
position.
broken.
Power
supply cable
is broken.
No sound
when or
buttons
2 pressed; no Damage of
signal on the the electric
display components,
screen. such as:
chips, silicon
control,
diode, etc.
Checking Steps
1. Eyeball whether the cable
connectors are in position on
the computer display board.
2. Eyeball whether the electric
current breaks between cable
connectors and program
selecting board.
3. Eyeball whether the line
connecting the program
selecting board and cable
connectors connecting points
breaks.
1. Check the S10 and ST1
terminals on the program
selecting board, X4 and X7
terminals on the power drive
board, and ST3 terminal on
the computer display board.
2. Check whether the back
connecting points on the
program selecting board are
broken; measure and test
whether the voltage between
the two ends of ST1 is 220 V.
3. Check the whether the back
connecting points on the
power drive board X4 are
broken; measure and test
whether the voltage between
X4-1 and X4-2 (or between J3
and J1 on the power board) is
220 V.
4. Measure and test the
silicon control diode(1S2) pin
voltage relative to the earth on
the power drive board：the left
is 22V DC; the right is 5V DC.
5. Measure and test X7-4 and
X7-5 terminal relative to the
X7-6 voltage： X7-4 is 22V DC;
X 7-5 is 5V DC.
6. Measure and test ST3-3
and ST3-2 terminal relative to
the ST3-1 voltage：ST3-3 is
22V DC; ST3-2 is 5V DC.

Troubleshooting

Instrument Solutions
1. Insert and connect in
Eyeballing position. If not, please go on
with step 2.
2. If electric current is
Eyeballing
broken, change the program
Multimeter
selecting board. If not, please
go on with step 3.
3. If electric current is
Eyeballing
broken, change the program
Multimeter
selecting board.
1. Insert and connect in
Eyeballing position. If not, please go on
with step 2.
2. If electric current is
broken, change the program
Eyeballing
selecting board. If the voltage
Multimeter
is 220V, please go on with
step 3.
3. If electric current is
broken, change the power
drive board; if the welding
point is not broken and the
Eyeballing voltage between J3 and J1 is
Multimeter not 220V, consider checking
whether the wiring harness
is broken; if the voltage is
220V, please go on with step
4.
4. If the voltage doesn't
comply with the requirement,
Eyeballing change power drive board; if
Multimeter it complies with the
requirement, please go on
with step 5.
5. If the voltage doesn't
comply with the requirement,
Eyeballing change power drive board; if
Multimeter it complies with the
requirement, please go on
with step 6.
6. If the voltage doesn't
comply with the requirement,
change the 6 connecting
Eyeballing
lines between X7 and ST3; if
Multimeter
it complies with the
requirement, please change
computer display board.
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