Chrysler 1997 Stratus Convertible RHD Service Manual page 542

8W - 42 - 6
DESCRIPTION AND OPERATION (Continued)
The A/C compressor clutch receives this current
and creates a magnetic field, energizing the clutch.
The A/C compressor clutch is case grounded to the
A/C compressor.
The A/C compressor clutch has a diode located in
it. This diode is used to control the induced voltage
resulting from the magnetic field collapsing when the
clutch is disengaged.
The A/C compressor clutch relay is also used by the
PCM to disengage the compressor in a Wide-Open
Throttle (W.O.T.) condition.
A/C PRESSURE TRANSDUCER
The A/C pressure transducer is located on the dis-
charge line near the compressor. Circuit C18 con-
nects from the Powertrain Control Module (PCM),
cavity 42, to the transducer. The PCM uses informa-
tion from the transducer to control operation of the
radiator fans.
Ground for the transducer is supplied on circuit
K4. This circuit connects to cavity 43 of the PCM.
The K4 circuit is spliced in with many of the sensors
used in the fuel injection system.
RADIATOR FAN OPERATION
The radiator fan system uses two relays located in
the Power Distribution Center (PDC). One relay is
used for LOW speed fan operation and the other is
for HIGH speed operation. The Powertrain Control
Module (PCM) controls the operation of the relays
depending on engine coolant temperature or A/C
operation.
Power for the coil side of both relays is provided on
circuit F18. This circuit is protected by a 10 amp fuse
located in cavity 9 of the Power Distribution Center
(PDC). Power for the contact side of the relays is pro-
vided on circuit A16. This circuit is protected by a 40
amp fuse located in cavity 17 of the PDC.
When LOW speed fan operation is required the
PCM grounds circuit C24. This causes the contacts in
the relay to CLOSE connecting circuits A16 and C23.
Circuit C23 connects from the relay to the low speed
portion of the fan motor. Ground for the motor is pro-
vided on circuit Z1, which terminates at the left strut
tower.
8W - 42 AIR CONDITIONING-HEATER
When HIGH speed fan operation is required the
PCM grounds circuit C27. This causes the contacts in
the relay to CLOSE connecting circuits A16 and C25.
Circuit C25 connects from the relay to the high speed
portion of the fan motor. Ground for the motor is pro-
vided on circuit Z1, which terminates at the left strut
tower.
BLOWER MOTOR OPERATION
With the ignition switch is in the RUN position,
power flows from the 30 amp fuse located in the
junction block, cavity 1, to the blower motor. Blower
motor speed is controlled by the fan control switch
located in the A/C—Heater control head, and by the
resistor block.
Blower motor LOW speed operation is accom-
plished on the C4 circuit. When the control switch is
moved to the LOW speed position, current flows from
the C1 circuit to the blower motor resistor. Power
flows through the blower motor back to the resistor.
Voltage is passed through the resistor to circuit C4.
Circuit C4 connects from the resistor block to the fan
control switch. Ground flows through the switch to
the Z1 circuit. The Z1 circuit terminates at a ground-
ing point located at the instrument panel.
The operation of blower motor M1 and M2 speed
operations is the same as the LOW speed except that
circuit C5 is used for the M1 speed, and circuit C6 is
used for the M2 speed operation.
Blower motor HIGH speed operation is accom-
plished on the C7 circuit. There are no resistors used
in the HIGH speed mode.
HELPFUL INFORMATION
Check the 10 amp fuse located in cavity 9 of the
junction block.
Check the 40 amp fuse located in cavity 17 of the
PDC.
Check the 30 amp fuse located in cavity 1 of the
junction block.
Check for a good ground at the instrument panel
left side cowl.
Check for a good ground at the left strut tower.
Check the A/C refrigerant level. The system will
not operate with a low level of refrigerant.
JX