12KHR-N
3 – 12
2. Troubleshooting of outdoor unit electric components
Does LED light?
NO
YES
NO
Does LED flash?
Normal
NO
YES
YES
NO
YES
NO
YES
Check 320VDC
between IPM pins
(20) and (24) ?
Short-circuit in DC fan motor
Short-circuit in IPM
Short-circuit in diode bridge
Blown fuse
Defective electrolytic capacitor
Wire disconnection, PWB pattern damage
Short-circuit in PAM IGBT (Q5)
Defective switching power supply circuit
Malfunction of 3-terminal regulator IC4, IC1
Short-circuit in expansion valve coil
Malfunction of transistor array IC7
Solder contact or other problems
Malfunction of 3-terminal regulator IC4, IC1
Microcomputer oscillator error
Malfunction of microcomputer reset IC
Malfunction of microcomputer
Malfunction of serial signal circuit
Check wiring between indoor and outdoor units.
Check switching
power supply
output of 12 VDC,
15 VDC ?
Check 5 VDC
output ?
Check 220-240VAC
input voltage.
