Service Manual

SiUS281811E Troubleshooting by Error Codes
Part 6 Service Diagnosis 245
Reference
Reference
Troubleshooting
CHECK 11 Refer to page 270.
CHECK 12 Refer to page 273.
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
YES YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
CHECK 12
CHECK 11
Is it cooling?
Is the low
pressure less or equal to 0.25 MPa
(36.3 psi)?
Is the
temperature
difference between the suction
pipe and the outdoor heat
exchanger greater than
20°C (68°F)?
Is the resistance
measured from suction pipe
thermistor disconnected from the
outdoor unit PCB
normal?
Is the voltage between
X18A pins (2) and (3) of outdoor
main PCB (A1P) less or equal to 1.0
VDC? (Low pressure sensor
output voltage)
Is the low pressure
sensor normal?
Short of refrigerant, closed stop
valve, or blocked cooling
system. Check the refrigerant
system.
Replace the outdoor main
PCB (A1P).
Replace the low pressure
sensor (S1NPL).
Replace the outdoor main
PCB (A1P).
Short of
refrigerant or blocked
cooling system. Check the
refrigerant system.
Replace the suction pipe
thermistor.
Replace the low pressure
sensor (S1NPL).