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FATC
29
TROUBLE SHOOTING
STEP
INSPECTION
ACTION
1
Check working of AC compressor as
per logic (correct speed)
Yes
Go to next step
No
Check software
2
Inspect refrigerant system performance
Perform refrigerant system performance
test (Refer AC system performance test)
is operating normal?
Yes
Operation is normal. (Recheck malfunc-
tion symptoms)
No
Go to next step
3
Verify whether malfunction is in blower
unit intake and condenser or another.
Are refrigerant’s high-pressure and low
pressure values both high?
Yes
Go to next step
No
Go to step 6.
4
Inspect blower unit intake is blower unit
intake clogged
Yes
Remove obstruction. (If air does not reach
evaporator within cooling unit, heat ex-
change does not occur, refrigerant
pressure becomes high, and therefore,
removal of obstruction is necessary.)
No
Go to next step
5
Inspect condenser is it okay?
Yes
Adjust refrigerant to specified amount.
(Excessive amount of refrigerant.)
No
Replace condenser, or repair and clean
condenser fins.
6
Verify whether malfunction is in expan-
sion valve, receiver/drier and
refrigerant lines or elsewhere
Are refrigerant’s high-pressure and low-
pressure values low?
Yes
Go to next step
No
Go to step 14
7
Verify whether malfunction is in expan-
sion valve and receiver /drier or
elsewhere immediately after A/C com-
pressor operates, does refrigerant’s
high-pressure value momentarily rise to
correct value, then fall and stay below
it? (Is there negative pressure on low-
pressure side?
Yes
Go to next step
No
Go to step 10.