Hi, forum users!
I repair the air conditioner. At first it highlighted error E6. The problem was on the board of the external unit of the air conditioner. There, the U102 ULN2003A microcircuit, which controls the relays, flew out. Due to a short circuit in this microcircuit, the standby power source did not start. I replaced the microcircuit, the duty room started, but an EE error appeared. The service manual does not clearly describe the cause of the error:
“During cooling and drying operation, compressor will stop while indoor fan will operate; During heating operation, the complete unit will stop”
As a solution to the problem, it is proposed to replace the board of the external unit.
I tried to find out the specific reason, but without success. After switching on, the voltage on large capacitors CO202, CO203 rises to the amplitude network (310V) and clicks relay K1, which shunts the charging resistor. After that, the yellow LED starts flashing 11 times. There are no control signals for the corrector and inverter microcircuits. How does the microcontroller determine the problem is not clear?
Maybe someone has already encountered a similar problem or has information regarding the algorithm for generating error signals? Tell me if it’s not difficult.