Mitsubishi Electric TRANE TPKA0A0121HA70A Service Manual page 25

9-4. TROUBLESHOOTING BY INFERIOR PHENOMENA
Phenomena
(1)Upward/downward vane
performance failure
(2)Receiver for IR wireless remote
controller
OCHT637
Cause
The vane is not downward during defrosting and heat
preparation and when the thermostat is OFF in HEAT
mode. (Working of COOL protection function)
Vane motor does not rotate.
• Defective vane motor
• Breaking of wire or connection failure of connector
Upward/downward vane does not work.
• The vane is set to fixed position.
Weak batteries of IR wireless remote controller
Contact failure of connector (CNB) on IR wireless
remote controller board
(Insert failure)
Contact failure of connector (CN90) on indoor con-
troller board (Insert failure)
Contact failure of connector between IR wireless
remote controller board and indoor controller board
25
Note: Refer to the manual of outdoor unit for the detail of remote
controller.
Normal operation (The vane is set to
horizontal regardless of remote control.)
Check
• Check the vane motor. (Refer to "9-6.
HOW TO CHECK THE PARTS".)
• Check for breaking of wire or connec-
tion failure of connector.
Normal operation (Each connector on
vane motor side is disconnected or set-
ting the fixed vanes by wired remote
controller.)
Replace batteries of IR wireless remote
controller.
–
Check contact failure of each connector.
If no problems are found of connector,
replace indoor controller board.
When the same trouble occurs even if
indoor controller board is replaced,
replace IR wireless remote controller
board.
Countermeasure
(left).