A/C System Tests - Honda Civic 2002-2003 Service Manual

Ale System Tests
Pressure Test
Test results
Related s.'Lrnptoms Probable cause Remedy
Discharge (high} After stopping compressor, pressure Air in system Recover, evacuate (see page 21-54),
pressure drops quickly, and then continues to
and recharge with specified amount
abnormally high
fal!.graduallv.
(see pooe 21 551.
Reduced or no air flow through • Clogged condenser or radiator
Clean
condenser fins Check fan voltage and rpm.
• Condenser or radiator fan not
Check fan direction.
workinQ properly
Line to condenser is excessively hot. Restricted flow of refrigerant in Replace restricted lines.
system
Discharge pressure High and low pressures are balanced Faulty compressor discharge Replace the compressor.
abnormally low soon after stopping compressor. Low
valve
side is higher than normal. Faultv compressor seal
Outlet of expansion valve is not Faulty expansion valve Replace the expansion valve.
frosted, low-pressure gauge indicates Moisture in system Recover, evacuate for at least
vacuum. 30 minutes, and recharge with
,
specified amount.
Suction (low)
Expansion valve is not frosted, and
1
Frozen expansion valve
.
Recover, evacuate for at least
pressure low-pressure line is not cold. Low- (Moisture in system)
i
30 minutes, and recharge with
abnormally low
pressure gauge indicates vacuum. Faulty expansion valve specified amount.
i· Reolace the expansion valve.
Discharge temperature is low, and the
Frozen evaporator
I
Run the fan with compressor off, then
air flow from vents is restricted. check evaporator temperature sensor.
Expansion valve is frosted. Cloooed exoansion valve Clean or reolace.
Receiver/dryer outlet is cool, and inlet Clogged receiver/dryer Replace receiver/dryer.
is warm (should be warm during
operation).
Suction pressure Low-pressure hose and check joint are
Expansion valve open too long Repair or replace.
abnormally high cooler than the temperature around
evaporator.
I
Suction pressure is lowered when Excessive refrigerant in system Recover, evacuate, and recharge with
condenser is cooled bv water.
soecified amount.
High and low-pressure are equalized • Faulty gasket Replace the compressor.
as soon as the compressor is stopped, • Faulty high-pressure valve
and both gauges fluctuate while • Foreign particle stuck in high·
running.
oressure valve
Suction and Reduced air flow through condenser. • Clogged condenser or radiator Clean
discharge
fins Check voltage and fan rpm.
pressures
• Condenser or radiator fan not
Check fan direction.
abnormallv high working properl
Suction and Low-pressure hose and metal end Clogged or kinked low-pressure Repair or replace .
discharge pressure . areas are cooler than evaporator.
. hose ·parts
abnormally low Temperature around expansion valve Clogged high-pressure line Repair or replace.
is too low compared with that around
receiver/dryer.
Refrigerant leaks Compressor clutch is dirty. Compressor shaft seal leaking Replace the compressor.
Compressor bolt(s} are dirty.
Leaking around bolt(s) Tighten bolt(s) or replace compressor.
Compressor gasket is wet with oil. Gasket leaking Replace the compressor.
(cont'd)
21-57