Chrysler Stratus LHD 1997, Интерактивное электронное руководство по эксплуатации

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the compressor clutch. The switch will then reset
once compressor surface temperature returns to nor-
mal.
SYSTEM AIRFLOW
The system draws outside air through the cowl
opening at the base of the windshield. Then it goes
into the plenum chamber above the Heater A/C unit
housing and passes through the evaporator. At this
point airflow can be directed either through or
around the heater core. This is done by adjusting the
blend-air door with the TEMP control on the control
head. After the air passes the blend air door, the air
flow is then directed from the PANEL, BI-LEVEL
(panel and floor), and FLOOR - DEFROST outlets.
Air flow velocity can be adjusted with the blower
speed selector switch on the control head.
Ambient air intake can be shut off by closing the
recirculating air door. This will recirculate the air
that is already inside the vehicle. This is done by
rotating the RECIRC. knob on the control head.
Rotating the MODE control knob to the Defrost/Floor
or Defrost setting on the control head will engage the
compressor. This will send refrigerant through the
evaporator, and remove heat and humidity from the
air before it goes through the heater core. The com-
pressor can also be engaged by depressing the A/C
button on the control head.
DIAGNOSIS AND TESTING
A/C PERFORMANCE TEST
The air conditioning system is designed to remove
heat and humidity from the air entering the passen-
ger compartment. The evaporator, located in the
heater A/C unit, is cooled to temperatures near the
freezing point. As warm damp air passes over the
fins in the evaporator, moisture in the air condenses
to water, dehumidifying the air. Condensation on the
evaporator fins reduces the evaporators ability to
absorb heat. During periods of high heat and humid-
ity, an air conditioning system will be less effective.
With the control module set to RECIRC, only air
from the passenger compartment passes through the
evaporator. As the passenger compartment air dehu-
midifies, A/C performance levels rise.
PERFORMANCE TEST PROCEDURE
Review Safety Precautions and Warnings in this
group before proceeding with this procedure. Air tem-
perature in test room and on vehicle must be 21° C
(70°F) minimum for this test.
NOTE: When connecting the service equipment
coupling to the line fitting, verify that the valve of
the coupling is fully closed. This will reduce the
amount of effort required to make the connection.
(1) Connect a tachometer and manifold gauge set.
Attach a thermal couple to the evaporator line.
(2) Set control to A/C, RECIRC, and PANEL, tem-
perature lever on full cool and blower on high.
(3) Start engine and hold at 1000 rpm with A/C
clutch engaged.
(4) Engine should be warmed up with doors and
windows closed.
(5) Insert a thermometer in the left center A/C
outlet and operate the engine for five minutes. The
A/C clutch may cycle depending on ambient condi-
tions.
(6) With the A/C clutch engaged, compare the dis-
charge air temperature to the evaporator line tem-
perature. The discharge air temperature should be
within –12°C (10°F).
(7) If the discharge air temperature fails to meet
the specifications. Refer to the System Charge Level.
COMPRESSOR CLUTCH COIL
(1) Verify battery state of charge.
(2) Connect an ammeter (0-10 ampere scale) in
series with the clutch coil terminal. Use a volt meter
(0-20 volt scale) with clip leads measuring voltage
across the battery and A/C clutch.
(3) With A/C control in A/C mode and blower at
low speed, start the engine and run at normal idle.
(4) The A/C clutch should engage immediately and
the clutch voltage should be within 2 volts of the bat-
tery voltage. If the A/C clutch does not engage, test
the fusible link.
(5) The A/C clutch coil is acceptable if the current
draw is 2.0 to 4.15 amperes at 11.5 to 12.5 volts at
clutch coil. This is with the work area temperature at
21°C (70°F). If voltage is more than 12.5 volts, add
electrical loads by turning on electrical accessories
until voltage reads below 12.5 volts.
(6) If coil current reads zero, the coil is open and
should be replaced. If the ammeter reading is 5
amperes or more, the coil is shorted and should be
replaced. If the coil voltage is not within two volts of
the battery voltage, test clutch coil feed circuit for
excessive voltage drop.
COMPRESSOR NOISE TEST
When investigating an air conditioning related
noise, you must first know the conditions when the
noise occurs. These conditions are: weather, vehicle
speed, in gear or neutral, engine temperature, or any
other special condition.
Noises that develop during air conditioning opera-
tion can often be misleading. For example: what
sounds like a failed front bearing or connecting rod,
may be caused by loose bolts, nuts, mounting brack-
JA
HEATING AND AIR CONDITIONING 24 - 5
DESCRIPTION AND OPERATION (Continued)