Mazda MX-5 1990 Workshop Manual page 760

TROUBLESHOOTING GUIDE
u
Case 6: Expansion valve stuck open
Measured pressure
Low-pressure side: Above 245 kPa (2.5 kg/cm
2
,
35.6 psi)
High-pressure side: 1,864-1,962 kPa (19-20 kg/cm2, 270-284 psi)
Condition
Insufficient cooling
CAUSE
EXPANSION
VALVE STUCK
OPEN
ACTION
REPLACE
EXPANSION
VALVE
05UOUX-030
05UOUX-088
1 . Check whether there is frost or heavy dew on the suction
pipe (between cooling unit and compressor).
2. If neither is found, refer to "Excessive refrigerant or insuffi-
cient condenser cooling"; page U-1S.
3. If either is found, replace the expansion valve.
(Refer to page U-33.)
Case 7: Faulty compressor
Measured pressure
Low-pressure side: 392-589 kPa (4-6 kg/cm
2
,
57-85 psi)
High-pressure side: 687-981 kPa (7-10 kg/cm
2
,
100-142 psi)
Condition
No cooling
CAUSE ACTION
MOISTURE
¢
EVACUATE
IN SYSTEM
SYSTEM
05UOUX-031
05UOUX-089
1. Run the engine at a first idle.
2. Verify that the magnetic clutch is ON when the
Ale
switch
and blower switch are ON.
3. If the magnetic clutch remains OFF, refer to "Magnetic
clutch does not operate"; page U-9.
U-17