Mazda 1996 626 Service Manual page 249

Pressure condition
High- and low-pressure-
side readings are higher
than normal
High- and low-pressure-
side readings are lower
than normal
High-pressure-side
reading is a little lower
than normal; low-pressure-
side reading is a little high­
er than normal
High-pressure-side
reading rises to normal
pressure range and then
drops below range; low-
pressure-side reading is
negative
No difference between
high- and low-pressure-
side readings
TROUBLESHOOTING GUIDE
Step Procedure
Check condenser fins.
(Refer to page G -59.)
Are they clogged or damaged?
Check all connections.
Are there any oil stains?
Check for leakage. (Refer to page
G -46.)
Are there any leaks?
Check heat-sensing tube.
Is it in its proper position and securely
connected to evaporator outlet pipe?
1. Turn A/C compressor off for about
10 minutes.
2. Turn A/C compressor on and imme­
diately check pressure reading.
Is pressure reading normal?
Check heat-sensing tube.
Is it properly installated?
Cause and Action
Insuffient condenser refrigeration
Yes
Clean or repair condenser fins
(Refer to page G~59)
Too much refrigerant
No
Discharge refrigerant and recharge to
proper amount (Refer to page G^45)
Insufficient refrigerant because of
leakage
Yes
Repair leaks and recharge refrigerant
to proper amount (Refer to page G -45)
No
Go to Step 2
Insufficient refrigerant because of
leakage
Yes
Repair leaks and recharge refrigerant
to proper amount (Refer to page G -45)
Insufficient charging
No
Recharge refrigerant (Refer to page G-45)
Expansion valve opening too wide be­
cause of expansion valve malfunction
Yes
Replace expansion valve
(Refer to page G -63)
Expansion valve opening too wide
No
because of improper heat-sensing
tube installation
Reinstall heat-sensing tube properly
(Refer to page G -64)
Expansion valve clogged because of
freezing by moisture
Yes
Discharge refrigerant, replace receiver/
drier (Refer to page G -60)
No
Go to Step 2
Expansion valve clogged with for­
eign material
Expansion valve opening too wide
because of expansion valve
Yes
malfunction or heat-sensing tube
leakage
Replace expansion valve (Refer to
page G -63)
Expansion valve opening too narrow
because of improper heat-sensing
tube installation
No
Reinstall heat-sensing tube
properly (Refer to page G -64)
Improper compression of A/C com­
pressor
Repair or replace A/C compressor
(Refer to page G -49)
G— 35