Toshiba MXZ-2DM40VA Service Manual page 44

• When the operation frequency does not go up from lowest frequency.
Check of HPS
MXZ-3DM50VA
1. Disconnect the connector CN681.
2. Check the resistance of HPS 1 minute after the outdoor unit breaker was turned OFF.
Check the resistance between
each terminal.
Reconnect CN681.
Turn ON the breaker to the indoor and the outdoor units.
3 minutes later, start EMERGENCY OPERATION.
Is HPS protection displayed
immediately after compressor
starts?
No
Normal
OBH739A
Infinity
Replace HPS.
Yes
Replace the outdoor control P.C. board.
44
CN681 Outdoor control P.C. board