Haier 4U25HS1ERA Service Manual - Page 99

>_]]VbTZR\ _^UZdZ_^Vb Trouble 3: Communication failure between indoor and outdoor start as per the wiring diagram, check if communication wiring is correct no re-wiring, and check again yes check if the communication port no connecting to the indoor/outdoor PCB is in open circuit if the power cable and the communication wire are too close, resulting in the wrong commission data no yes yes replace the communication connection wire, check again adjust the distance and check again PCB is faulty, replace and check again Trouble 4: Indoor PCB EEPROM data is wrong 1.If the failure occurs when being electrified for the first time, that shows EEPROM (8-bit pin) not fixed firmly or damaged. 2.If the failure occurs when running, that shows EEPROM is faulty and need to be replaced. Trouble 5: Indoor repeated unit number 1.Firstly query the unit number: switch off the unit, press SLEEP for about 15 seconds until the buzzer sounds 5 times, on the display panel there will be digit, which is indoor number. By this method,you can check if there is repeated unit number, if yes, please re-set the number as per the unit number setting procedure. 2.Re-set the unit number directly, the unit with outdoor pipe A is No. 1; the unit with outdoor pipe B is No. 2; the unit with pipe C is No.3 Trouble 6: Indoor fan motor failure, AC fan motor has not 50Hz zero-crossing detection start check if the fan no motor input connection is fixed badly(CN3 on PCB) yes replace fan motor input port, cut off power supply and be electrified again check the fan motor feedback wire is no fixed badly (CN23 on PCB) yes replace fan motor feedback port, cut off power supply and be electrified again Trouble 7: Outdoor unit failure Check the failure code on outdoor indicator board (5-lamp) PCB is faulty and replace it -98-