Troubleshooting - Carrier 40MBC/38MAQ Installation Instructions Manual

TROUBLESHOOTING

For ease of service, the systems are equipped with diagnostic code
display LEDs on both the indoor and outdoor units. The outdoor
diagnostic display consists of two LEDs (Red and Green) on the
outdoor unit board and is limited to a few errors. The indoor
diagnostic display is a combination of flashing LEDs on the
INDOOR UNIT DIAGNOSTIC GUIDES
Operation Lamp Timer Lamp
☆
X
1 time
☆ 2 times X
☆ 4 times X
5 times X
☆
6 times X
☆
7 times X
☆
☆ 8 times X
☆ 1 time O
2 times O
☆
3 times O
☆
4 times O
☆
☆ 5 times O
☆ 6 times O
☆ 7 times O
8 times O
☆
9 times O
☆
10 times O
☆
☆ 1 time ☆
☆ 2 times ☆
3 times
☆ ☆
4 times
☆ ☆
5 times
☆ ☆
☆ 6 times ☆
☆ 7 times ☆
☆ 8 times ☆
☆ (flash)
O (light) X (off)
For additional diagnostic information, refer to the Service Manual.
OUTDOOR UNIT DIAGNOSTIC GUIDES
LED2 LED1
(Green) (Red)
O X
X O
O
☆
X
☆
O O
X
☆
O
☆
☆ ☆
☆ = Flashing, X = Off
For additional diagnostic information, refer to the Service Manual
Table 7—Indoor Unit Diagnostic Guides
Display LED Status
E0 Indoor unit EEPROM error
E1 Communication malfunction between indoor and outdoor units
E3 Indoor fan speed has been out of control
E4 Indoor room temperature sensor T1 open circuit or short circuit
E5 Evaporator coil temperature sensor T2 open circuit or short circuit
EC Refrigerant leakage detection
EE Water--- level alarm malfunction
F0 Current overload protection
F1 Open circuit or short circuit of outdoor ambient temperature sensor T4
F2 Open circuit or short circuit of condenser coil temperature sensor T3
F3 Open circuit or short circuit of Compressor discharge temperature sensor T5
F4 Outdoor unit EEPROM error
F5 Outdoor fan speed has been out of control
F6 T2B sensor error
F7 Lifting --- panel communication error
F8 Lifting --- panel malfunction
F9 Lifting --- panel is not closed
P0 IPM malfunction
P1 Over voltage or over low voltage protection
P2 High temperature protection of compressor top
P3 Outdoor low temperature protection
P4 Inverter compressor drive error
P5 Mode conflict
P6 Compressor low--- pressure protection
P7 Outdoor IGBT temperature sensor error
Table 8—Outdoor Unit Diagnostic Guides
Indoor Unit display Failure Mode
Standby, normal
Operation, normal
E5 Compressor drive board EEPROM error
P0 IPM malfunction or IGBT over---strong current protection
P1 Over voltage or too low voltage protection
P4 Inverter compressor drive error
P4 Inverter compressor drive error
P4 Communication malfunction between main control board and driver board
display panel or the front of the unit. If possible, always check the
diagnostic codes displayed on the indoor unit first.
The diagnostic codes displayed in the indoor and outdoor units are
listed in the tables below.
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