Service manual
3-12
AY-ZP35PR
4 Compressor check Measure compressor coil resistance
(for each phase of U, V and W).
Use multi-meter or digital tester capa-
ble of displaying two digits right of the
decimal point (0.01Ω).
Resistance value at 20°C --- 0.65Ω Correct connections at compres-
sor terminals.
Replace compressor.
5 Expansion valve check Measure expansion valve coil resis-
tance.
Each phase 46±3Ω (at 20° Replace expansion valve.
6 Final check Turn off power, and connect compres-
sor cords to compressor.
Operate air conditioner.
Measure DC voltage between IPM
pins (20) and (24).
Compressor should operate nor-
mally.
280 VDC or higher.
Replace control PWB.
Replace outdoor unit thermistor.
Replace compressor (in case of
compressor lock).
C)
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 IC3, IC2.
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.
2. Troubleshooting of outdoor unit electric components
2 Inverter DC power supply
voltage check
Measure DC voltage between IPM
pins (31) and (35).
.BWP lortnoc ecalpeRCDV 023
Replace diode bridge.
Correct soldered section of Fas-
ten tabs (T1, T2, T5 - T3) on con-
trol PWB and IMP (S, C, R).
(Repair solder cracks.)
3 IPM circuit check Check that 3 lamps (load) light.
Check position detection voltage (+15
V, 5 V) on control PWB.
Each voltage should be normal.
All 3 lamps (load) should light with
same intensity.
Replace control PWB.
No ydemeRnoitidnoc/eulav lamroNdohtem kcehCmetI