Pioneer YN018GMFI16M2D Service Manual page 47

9.3.2.9 IPM module protection (ODU P4)
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
36KBtu/h
Yes
Check whether the
connecting line between main
board and the IPM module is
connected tightly
Yes
Check whether the
connecting line of the
compressor is connected
correctly or tightly
Yes
Replace the IPM module,
check whether the system
can work normally?
No
Replace the main board;
check whether the system
can work normally?
No
Replace the compressor,
check whether the system
can work normally?
Yes
No
Connect it tightly,
No
check ok or not?
No
Connect it well,
No
check ok or not?
No
Yes
Yes
Yes
Trouble is solved
Check whether the
input power supply is
No
correct? 220-240V, 1N,
60Hz
No
Yes
Check whether the
power supply line is
No
connected correctly
and tightly
Yes
Check whether the
lines in E-part box are No
connected tightly
Yes
Check whether the bridge rectifiers
are normal? Use the multimeter to
measure the resistance between
each two terminals, check whether
there is the condition that value of
resistance is 0
Yes
Check whether the connecting line of
every reactor is normal? If the line is
broken, the resistance of the two
ports is ∞（models except for M4OC-
36HRDN1-M）；Check whether the
PFC module broken (for M4OC-
36HRDN1-M)
Regulate it to correct,
then check whether the
system can work
normally?
Connect it correctly
and tightly, check ok
or not?
No
Connect it tightly,
check ok or not?
No
No
Replace the bridge rectifiers
No
Replace the connecting line or
reactor or replace the PFC
module(for M4OC-36HRDN1-M)