Carrier 38QUS012D8S - Page 130

Troubleshooting
Electrical Control System 128
2.4.4.9. P0 Malfunction
Malfunction conditions
When the voltage signal te IPM sends to compressor drive
chip is not normal, the LED displays “P0” and the unit turns off.
Possible causes
● Wiring mistakes
● Faulty IPM board
● Faulty outdoor fan assemby
● Compressor malfunction
● Faulty outdoor PCB
First, test the resistance between every two ports of U, V, the W of the IPM and P, N. If any of the results is 0
or close to 0, the IPM is defective. If not, follow the following procedure: