Midea MV5-X252W/V2GN1 Service Manual page 99

V5 X VRF 50/60Hz
4.23 xF1 Troubleshooting
4.23.1 Digital display output
'x' is a placeholder for the compressor system (compressor and related electrical components), with 1 representing
compressor system A and 2 representing compressor system B.
4.23.2 Description
 1F1 indicates compressor A DC bus voltage error.
 2F1 indicates compressor B DC bus voltage error.
 When the DC bus voltage is outside the range 300-800V continuously for 10 seconds, the system displays the F1 error
code and all units stop running.
 Error code is only displayed on the unit with the error.
4.23.3 Possible causes
 Loosened wiring within electric control box.
 Power supply abnormal.
 Contactor damaged.
 Three-phase bridge rectifier damaged.
4.23.4 Procedure
xF1
Voltage between +15V and N pins of
inverter module voltage monitor port on
main PCB is abnormal
No
Voltage between P and N pins of inverter
module voltage monitor port on main
PCB is abnormal
98
Yes
1
Yes
2
 Reactor damaged.
 DC filter board damaged.
 Inverter module damaged.
 Main PCB damaged.
Wires between
inverter module
voltage monitor port
on main PCB and
voltage monitor port
on inverter module
3
are loose
Yes
Ensure the wires are
connected properly
Replace outdoor
main PCB
No
Replace the inverter module
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