L5" Outdoor Unit: Inverter Compressor Abnormal - Panasonic U-4..6ML5XPQ Service Manual

Troubleshooting by Indication on the Remote Controller
L5
3.36 " " Outdoor Unit:
L5
Remote
Controller
Display
Applicable U-4..6ML5DPQ, U-4..6ML5XPQ
Models
Method of Malfunction is detected from current flowing in the power transistor.
Malfunction
Detection
Malfunction When an excessive current flows in the power transistor.
(Instantaneous overcurrent also causes activation.)
Decision
Conditions
Supposed
Causes
Troubleshooting
Higher voltage than actual is displayed when the inverter output voltage is checked by tester.
184
Inverter Compressor Abnormal
Defect of compressor coil (disconnected, defective insulation)
Compressor start-up malfunction (mechanical lock)
Defect of inverter PC board (A2P)
Be sure to turn off power switch before connect or disconnect connector,
Caution or parts damage may be occurred.
Compressor inspection
The compressor's
coil is disconnected or the
insulation is
defective.
NO
Disconnect the connection
between the compressor and
inverter. Make the power
transistor check mode setting
ON by service mode.
Inverter
output
voltage check
Inverter output
voltage is not balanced.
(Normal if within ±5V Must
be measured when
frequency
is stable.
NO
There is
instantenious power
drop.
NO
YES
YES
YES
Urban Multi ML5 · Mini UM · Heat Pump
Replace the compressor.
Replace the inverter unit (A2P).
Correct power supply.
Compressor inspection
Inspect according to the diagnosis
procedure for odd noises, vibration
and operating status of the
compressor.
Troubleshooting
(V2812)