Mitsubishi Electric MR-B46Z-W-C Service Manual page 35

Inverter-related indication "Compressor does not operate"
Error
Abnormality
code
• Failed wiring
E56
continuity
• Trouble of the
control board
Compressor
Point+2 (to measure resistance)
For checking the connection
Lead wire assembly
to compressor
E57
Inverter drive
module abnor-
mality
OAH162
Possible cause Symptom
• Poor connection The compres-
of connectors sor cannot be
related to com- activated for
pressor (on the more than 1.5
board and the hours.
compressor.)
• Failure in wiring
connecting of the
compressor
• Trouble of con-
trol board
• Trouble of com-
pressor
CN50G
Control board
Point+1 (to measure resistance)
For checking the lead wire
assembly to compressor
Overcurrent is
Failure of the
detected in the
inverter drive mod-
inverter drive
ule in the control
module before
starting the com-
P.C. board
pressor, and the
compressor does
not start rotating.
Corrective measures
1. Locate the trouble and decide on the measures.
• Decide the measures by checking the followings.
(1) Poor connector connections.
(On the board and the compressor.)
(2) Winding resistance of compressor
2. Flowchart of troubleshooting
start
The connector CN50G on the
control board is properly
connected?
Yes
The connector of compressor
is properly connected?
Yes
Remove the CN50G
connector on the control
board, and measure the
winding resistance on the
compressor. , and
(Point1). Is the resistance
approx.
Yes
Is compressor being
energized at startup?
Yes
Replace the compressor.
3. Recheck after corrective measures
• After any measures are taken, unplug and plug power cord
again to check that the compressor operates properly.
• If the compressor operates properly for more than 1 minute
after power cord is plugged again, it is presumed that the
cause of trouble is eliminated.
*If the cause of trouble cannot be eliminated,
played again 1 minute later after the power cord is plugged
again.
*If the control board has been replaced,
played even though the cause of trouble is still not eliminated.
In such a case, perform the ice making test operation to check
what the error is. At the same time, also check that the com-
pressor is operating for more than 3 minutes and each com-
partment is getting cooled.
Replace the control board.
35
Check
No
Connect it properly.
No
Measure the
winding resistance
of compressor
No No
between each
terminal (Point 2).
Is the resistance
approx.
Yes
Replace the lead wire assembly.
No
Replace the control board.
Replace the control P.C. board
only when the error display keeps
blinking even though all the above
mentioned connectors are properly
connected.
E56
E56
will not be dis-
Treatment
Replace the
compressor.
will be dis-