filter the refrigerant. The orifice tube is used to meter the flow of
liquid refrigerant into the evaporator core.
HIGH PRESSURE CUT-OUT SWITCH
High pressure cut-out switch is located on compressor
discharge line, near compressor. On Dakota and Ram Pickup, it is
connected in series with the clutch cycling pressure switch and
control panel, between ground and PCM.
On Durango, it is connected in series with the electronic
cycling clutch switch, low pressure cut-out switch and control panel,
between ground and PCM. PCM controls compressor clutch operation.
On all models, when discharge pressure reaches 450-490 psi
(31.6-34.5 kg/cm
), high pressure cut-out switch interrupts A/C
request signal to PCM. PCM de-energizes compressor clutch relay,
disengaging compressor clutch. When discharge pressure drops to 270-
330 psi (23.2-19 kg/cm
) switch will close, thus restoring A/C request
signal to PCM.
HIGH PRESSURE RELIEF VALVE
High pressure relief valve is located on compressor manifold.
Valve vents system pressure if pressure is greater than 500-600 psi
(35.1-42.2 kg/cm
). Valve will reset when pressure decreases to 400
psi (28.1 kg/cm).
LOW PRESSURE CUT-OUT SWITCH OPERATION
Durango
Low pressure cut-out switch is located on suction line near
firewall. It is connected in series with the electronic cycling clutch
switch, high pressure cut-out switch and control panel, between ground
and PCM. PCM controls compressor clutch operation.
When discharge pressure reaches 10 psi (.7 kg/cm
), switch
interrupts A/C request signal to PCM. PCM de-energizes compressor
clutch relay, disengaging compressor clutch. When discharge pressure
increases to 13-27 psi (.9-1.9 kg/cm
), switch will close thus
restoring A/C request signal to PCM.
ADJUSTMENTS
TEMPERATURE CONTROL CABLE ADJUSTMENT
Dakota & Durango
1) Ensure temperature control cable housing and core are
connected at both A/C-heater control panel and A/C-heater assembly.
Ensure A/C-heater control panel is installed.
2) Rotate temperature control knob so that knob pointer is at
12 o'clock position. Pull temperature control knob straight out from
A/C-heater control panel until perimeter of knob (not knob pointer)
protrudes about .25" (6 mm) from face of A/C-heater control panel.
3) Rotate temperature control knob clockwise so that knob
pointer is at one o'clock position. Push in on knob slightly and
continue rotating knob to its full clockwise stop. Place knob pointer
at a position about .32" (8 mm) beyond end of Red stripe. Release
knob. If knob is pointing at about .32" (8 mm) beyond end of Red
stripe, go to next step. If knob is not pointing at about .32" (8 mm)
beyond end of Red stripe, go back to step 2) and repeat adjustment
procedure.
4) Rotate temperature control knob counterclockwise so that
knob pointer is at 12 o'clock position. Push temperature control knob
straight into A/C-heater control panel until perimeter of knob (not
Fully depress brake pedal and rotate brake switch
counterclockwise approximately 30 degrees. Remove brake switch from
bracket. Depress lock tabs holding brake switch mounting bracket and
separate harness connector from brake switch.
Installation
1) Before installing brake switch, reset adjustable plunger
by pulling on plunger head until plunger reaches end of travel.
Connect harness connector to brake switch. Depress brake pedal and
insert brake switch into keyed hole in mounting bracket. Rotate brake
switch clockwise into locked position.
2) Gently pull back on brake pedal until pedal will go no
further. This causes the brake switch plunger to ratchet backward to
the correct position. No further adjustment is required.
SPEED CONTROL SERVO
Removal (Except Ram Van & Ram Wagon)
1) Disconnect negative battery cable. Disconnect electrical
connector and vacuum hose from servo. Using finger pressure only, push
servo cable connector from throttle body bellcrank pin. DO NOT pull
cable connector perpendicular to bellcrank.
2) Remove 2 servo cable mounting nuts. Pull servo cable
sleeve away from mounting bracket to expose cable retaining clip.
Remove retaining clip. Remove servo.
Removal (Ram Van & Ram Wagon)
1) Disconnect negative battery cable. Remove engine cover.
Remove air cleaner assembly. Using finger pressure only, push servo
cable connector from throttle body bellcrank pin. DO NOT pull cable
connector perpendicular to bellcrank.
2) Remove right headlight assembly. Disconnect vacuum hose
and electrical connector at servo. Remove 2 servo mounting bracket
bolts. Remove 2 servo cable mounting nuts. Pull servo cable sleeve
away from mounting bracket to expose cable retaining clip. Remove
retaining clip. Remove servo.
Installation (All Models)
With throttle in full open position, align hole in speed
control cable sleeve with hole in servo pin. Install retaining clip.
To complete installation, reverse removal procedure. Tighten mounting
bolts/nuts to 75 INCH lbs. (8.5 N.m).
SPEED CONTROL SWITCHES
Removal & Installation
Turn ignition off. Disconnect negative battery cable. Wait 2
minutes for air bag system to discharge reserve voltage. Remove 2
screws holding air bag assembly to steering column. Separate air bag
assembly from steering column and disconnect air bag, horn and speed
control switch connectors. Remove screws securing speed control switch
to air bag assembly. Separate speed control switch from air bag
assembly. To install, reverse removal procedure.
WIRING DIAGRAMS