Carrier 42QHC009DS Service Manual

Also see for 38QHC009DS series: Installation manual Owner's manual Owner's manual Installation manual

33Index1:1:Indoor or Outdoor DC Fan Motor(control chip is in fan motor)Power on and when the unit is in standby, measure the voltage of pin1-pin3, pin4-pin3 in fan motorconnector. If the value of the voltage is not in the range showing in below table, the PCB must hasproblems and need to be replaced.DC motor voltage input and outputNO. Color Signal Voltage1 Red Vs/Vm 280V~380V2 --- --- ---3 Black GND 0V4 White Vcc 14-17.5V5 Yellow Vsp 0~5.6V6 Blue FG 14-17.5V2. Outdoor DC Fan Motor (control chip is in outdoor PCB)Power on ,and check if the fan can run normally, if the fan can run normally, the PCB must hasproblems and need to be replaced, If the fan can’t run normally, measure the resistance of each twopins. If the resistance is not equal to each other, the fan motor must have problems and need to bereplaced, otherwise the PCB must has problems and need to be replaced.3. Indoor AC Fan MotorPower on and set the unit running in fan mode at high fan speed. After running for 15 seconds,measure the voltage of pin1 and pin2. If the value of the voltage is less than 100V(208~240V powersupply)or 50V(115V power supply), the PCB must has problems and need to be replaced.