Friedrich MRM09Y1J, Service & Parts Manual

Page: 93 / 135

93 PB
TROUBLESHOOTING
Malfunction of blocked Protection of IDU Fan Motor H6
Measure the voltage of this foot to neutral
wire on the mainboard
smoothly
Stir the blade
with a tool to see whether
the blade rotates
Troubleshooting for
H6 malfunction
End
Replace PG motor
yes
no
Is malfunction
eliminated
yes
no
Insert the control
terminal of PG
no
no
motor tightly
Check if the connection
Is malfunction
Reinstall the blade and
motor correctly
no
eliminated
no
yes
yes
no
yes
yes
Is the motor
no
started up
Is malfunction
eliminated
yes
yes
yes no
yes
Turn on the
unit again ; measure whether the output
voltage on control terminal for PG motor
is more than 50V within 1 min after the
louvers are opened
Is malfunction
eliminated
Tighten the screw; reassemble the blade, motor
and shaft bearing rubber base sub-assy to make
sure there is no foreign object between them
Replace the mainboard
with the same model.
Check if the connection of PG
motor feedback terminal is firm.
of PG motor control
terminal is firm.
9-24k
36k
Connect power and restart the unit.
Test whether the voltage between
terminal 1 and terminal 2
of motor interface is within
280~310VDC.
Then check whether the voltage
between terminal 2 and terminal 3
of the motor interface is 15VDC.
Then check whether there is voltage
between terminal 2 and terminal 4
of the motor interface