Mazda 626 Station Wagon, Workshop Manual

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TROUBLESHOOTING
STEP INSPECTION
ACTION
7 CHECK TO SEE WHETHER MALFUNCTION IS
IN EXPANSION VALVE AND RECEIVER/DRIER
OR ELSEWHERE
• Immediately after A/C compressor operates,
does refrigerant 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.
8 CHECK TO SEE WHETHER MALFUNCTION IS
IN EXPANSION VALVE OR RECEIVER/DRIER
• Turn A/C switch off and let air conditioner stop
for 10 minutes.
• Start engine.
• Turn both A/C switch and fan switch on.
• Does malfunction occur after A/C compressor
turns on?
Yes Go to next step.
No Install the manifold gauge set and vacuum pump.
Start the vacuum pump and let it operate for 30
minutes. Replace receiver/drier, then go to Step
21. (Since water has intermixed in receiver/drier
and it is saturated, replacement Is necessary.)
9
VERIFY THAT EXPANSION VALVE
HEAT-SENSING TUBE WITHIN COOLING UNIT
IS POSITIONED SECURELY AND CORRECTLY
• Is expansion valve heat-sensing tube within
cooling unit securely installed proper position?
Yes Replace expansion valve, then go to Step 21.
(Since valve closes too much, replacement is
necessary.) |
No Install heat-sensing tube securely in proper
position, then go to Step 21.
10 INSPECT REFRIGERANT LINES
• Inspect refrigerant lines.
— Is piping free of damage and cracks?
— Are piping connections free of oil grime?
(Visual inspection)
— Are piping connections free of gas leakage?
— Are piping installation points on condenser
free of gas leakage?
— Are piping installation points on
receiver/drier free of gas leakage?
— Are piping installation points on A/C
compressor free of gas leakage?
— Are piping installation points on cooling unit
free of gas leakage?
‘ Perform gas leak inspection using gas leak
tester.
• Are above items okay?
Yes Go to next step.
No
If piping or A/C component is damaged or
cracked, replace it. Then go to Step 21 . If there is
no damage, go to Step 13.
11
INSPECT EVAPORATOR PIPING
CONNECTIONS IN COOUNG UNIT FOR GAS
LEAKAGE
• Are piping connections for evaporator in
cooling unit free of gas leakage?
Yes If the vane makes a noise, add 10 ml {10 cc,
0.338 fl
0 2
} of compressor oil to the A/C i
compressor. Verify that the noise is no longer
heard.
Adjust refrigerant to specified amount, then go to
Step
21.
No
If piping is damaged or cracked, replace it. Then
go to Step 21 . If there is no damage, go to next
step.
12 INSPECT EVAPORATOR PIPING
CONNECTIONS IN COOLING UNIT FOR
LOOSE
• Are piping connections for evaporator in
cooling unit loose?
Yes Tighten connections to specified torque. If the
vane makes a noise, add
10 ml {10 cc,
0.338 fl oz} of compressor oil to the A/C
compressor. Verify that the noise is no longer
heard. Adjust refrigerant to specified amount, then
go to Step 21.
No If the vane makes a noise, add 10 ml {10 cc,
0.338 fl oz} of compressor oil to the A/C
compressor. Verify that the noise is no longer
heard.
Replace O-ring on piping, adjust refrigerant to
specified amount, then go to Step 21 .
U -3 2