Gree JKFD15CR/Na-M, Руководство по обслуживанию

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GREE Air-ccoled Closed Control Unit Service Manual
102
Possible Causes:
（
1
）
Mainboard is burnt out;
（
2
）
Protective tube is damaged;
（
3
）
Wrong wiring
Possible causes: remove electric box to check the mainboard. If it is burnt out, the
mainboard shall be replaced.
Check if protective tube breaks. If so, the protective tube shall be replaced. Check if null
wire or live wire of power cord is short-circuited. If so, remove the malfunction and re-energize
the unit.
Check if the wiring is correct according to wiring diagram. Check the conductivity of wire by
universal meter.
Once the unit is energized, check if power indicators D3, D30 are bright. If they are bright,
mai5V is correct. Buzzer of mainboard will sound after energization. If it is not sound,
the mainboard has malfunction and needs to be replaced. Check +5V
、
+12V
、
-12V by
universal meter. If they are normal, transformer and rectifier circuit are normal, or else they
need to be replaced. Check communication indicator D4 of mainboard. If D4 is blinking, the
communication between mainboard 2 and mainboard 1 is normal. If communication indicator
D12 blinks, communication between mainboard 2 and touchable screen is normal. If it is
abnormal, check if the communication wire is connected correctly.
Conclusion: if null wire and live wire are short circuited, protective tube will break or
mainboard will be burnt out. If wiring is loose or breaks, communication of mainboard will be
abnormal and the unit will not operate.