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38MBR: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
35
J0 Malfunction
Troubleshooting
Error Code
J0
Malfunction decision conditions
When the evaporator coil is more than 140°F(60°C), the unit stops. It starts up again only when the evaporator
coil is less than 129°F(54°C).
Supposed Causes
• Faulty evaporator coil temperature sensor
• Dirty heat exchanger
• Faulty fan
• Faulty PCB
J0 displayed
Evaporator high
temperature protec
Ɵ
on
Is the compressor
opera
Ɵ
ng
?
Is the connec
Ɵ
on
between T2 and the
PCB in working
order
?
Has T2 and T2B been
reversed
?
Correct the connec
Ɵ
on.
No
Is the outdoor
ambient temp. higher
than 86°F (30°C)
?
Yes
Stop the unit.
Yes
No
Is the resistance of
T2 normal according
to *Appendix 1
?
Yes
No
Replace the
temp. sensor.
Is the air outlet
blocked
?
No
Clean the air outlet.
Yes
Is the indoor fan
running normally
?
No
Refer to the Fan Speed
Out of Control
malfunc
Ɵ
on solu
Ɵ
on.
Find the cause and
resolve the problem.
No
Are the heat exchanger
and
Įů
ter dirty
?
Yes
Clean the heat
exchanger and
Įů
ter.
Yes
Replace the
indoor main PCB.
No
Yes