Mitsubishi Electric MXZ-2C30VA Service Manual page 108

• When the operation frequency does not go up from lowest frequency.
Check of HPS
MXZ-3C68/4C71/4C80/5C100/6C120/6C122VA
MXZ-4C80/5C100VA2
1. Disconnect the connector CN681.
2. Check the resistance of HPS 1 minute after the outdoor unit power supply was turned OFF.
Check the resistance between
each terminal.
0Ω
Reconnect CN681.
Turn ON the power supply to the indoor and outdoor units.
3 minutes later, start EMERGENCY OPERATION.
Is HPS protection displayed
immediately after compressor
starts?
No
Normal
OBH584G
Infinity
Replace HPS.
Yes
Replace the electronic control P.C. board, control
P.C. board or the outdoor control P.C. board.
108
MXZ-3C/4C/5C
Electronic
CN681
control P.C. board
MXZ-6C120 MXZ-6C122
Outdoor control
Control P.C. board
P.C. board