Mazda 1996 626, Service Manual, Page: 249 / 533

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