Carrier 38MGRBQ18B-3 - Page 68

38MGRBQ: Service Manual
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68
DIAGNOSIS AND SOLUTION (CONT)
P6/PC 00 (Inverter module (IPM) malfunction) diagnosis and solution
Troubleshooting
ERROR CODE
P6/PC 00
MALFUNCTION DECISION
CONDITIONS
When the voltage signal that the IPM sends to the compressor drive chip is abnormal, the display LED displays
P6 and unit turns off.
SUPPOSED CAUSES
Wiring mistake
IPM malfunction
Faulty outdoor fan assembly
Compressor malfunction
Faulty Outdoor PCB
IPM module protection
Check whether the voltage range
of P-N on IPM module is normal
DC277-356V for 18-27KBtu/h;
DC277-410V for 36-48KBtu/h
Yes
Yes
No
Yes
Check whether the input
power supply is correct
208-230V, 1N, 60Hz
No No
Regulate it to correct, then
check whether the system
can work normally
Check whether the
power supply line is
connected correctly and
tight
Yes
Connect it correctly
and tight
No
Is the connecting line between
main board and the
IPM module is well
connected?
Yes
No
No
No
Is the connecting compressor
line connected
correctly and tight?
Replace the IPM module,
check whether the system can
work normally?
No
No
Replace the main board; check
whether the system can work
normally
No
Replace the compressor, check
whether the system can work
normally
Check whether the lines
in E-part box are
connected tight
Yes
No
No
Yes
No
Replace the bridge rectifiers
Check whether the bridge rectifiers are
normal. Use the multimeter to measure
the resistance between the two
terminals. Check whether the resistance
value is 0.
Replace the connecting line or
reactor or replace the PFC
module(for M4OF-36HFN1-
M&M5OF-48HFN1-M)
Yes
No
No
Yes
Problem solved
Check if the outdoor fan
runs properly or the outdoor
unit ventilation is good.
No
Refer to the Fan Speed is Out
of Control. Determine the
cause and resolve.
Yes
Yes
Yes
Connect it correctly
and tight
Connect it correctly
and tight
Connect it correctly
and tight
Is the connecting line for every reactor
normal? If the line is broken,
the resistance of the two ports is
ь
Check if the PFC broken module
(for M4OF-36HFN1-M & M5)F-48HFN1-m)