Chrysler 300M, Dodge Interpid. Manual — part 395

INSTALLATION

(1) Align pin in back of field coil with hole in com-

pressor end housing, and position field coil into place.
Make sure that lead wires are properly routed, and
fasten the diode and coil wire bracket with retaining
screw.

(2) Install field coil retaining snap ring with Snap

Ring Pliers (C- 4574). Press snap ring to make sure
it is properly seated in the groove.

NOTE: The bevel side of the snap ring must be out-
ward. Also both eyelets must be to the right or left
of the pin on the compressor.

CAUTION: If snap ring is not fully seated it will
vibrate out, resulting in a clutch failure and severe
damage to the front face of the compressor.
Do not mar the pulley frictional surface.

(3) Install pulley assembly to compressor. If neces-

sary, tap gently with a block of wood on the friction
surface (Fig. 5).

(4) Install pulley assembly retaining snap ring

(bevel side outward) with Snap Ring Pliers (C-4574).
Press the snap ring to make sure it is properly
seated in the groove.

NOTE: The bevel side of the snap ring must be fac-
ing outward.

(5) If the original front plate assembly and pulley

assembly are to be reused, the old shim(s) can be
used. If not, place a trial stack of shims, 2.54 mm
(0.10 in.) thick, on the shaft against the shoulder.

(6) Install front plate assembly onto shaft.
(7) If installing a new front plate and/or pulley

assembly, the gap between front plate and pulley face
must be checked. Use the following procedure:

(a) Attach a dial indicator to front plate so that

movement of the plate can be measured.

(b) With the dial indicator zeroed on the front

plate, energize the clutch and record the amount of
movement.

(c) The readings should be 0.35 to 0.65 mm

(0.014 to 0.026 in.). If proper reading is not
obtained, add or subtract shims until desired read-
ing is obtained.
(8) Install compressor shaft bolt. Tighten to 17.5 ±

2 N·m (155 ± 20 in. lbs.).

NOTE: Shims may compress after tightening shaft
nut. Check air gap in four or more places to verify if
air gap is still correct. Spin pulley for final check.

(9) Install the accessory drive belts (Refer to 7 -

COOLING/ACCESSORY

DRIVE/DRIVE

BELTS

-

INSTALLATION) or (Refer to 7 - COOLING/ACCES-
SORY DRIVE/DRIVE BELTS - INSTALLATION).

A/C COMPRESSOR CLUTCH
RELAY

DESCRIPTION

The compressor clutch relay is located in the Power

Distribution Center (PDC) in the engine compart-
ment. Refer to the PDC label for relay identification
and location.

OPERATION

The a/c compressor clutch relay is a electromechan-

ical device that switches battery current to the a/c
compressor clutch coil when the Powertrain Control
Module (PCM) grounds the coil side of the relay. The
PCM responds to inputs from the a/c heater control
(Manual Temperature Control, or Automatic Temper-
ature Control) , the Body Control Module (BCM), and
the a/c pressure transducer.

The compressor clutch relay cannot be repaired

and, if faulty or damaged, it must be replaced.

Fig. 5 INSTALLING PULLEY ASSEMBLY

1 - PULLEY ASSEMBLY
2 - WOOD BLOCK

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24 - 11

A/C COMPRESSOR CLUTCH (Continued)

DIAGNOSIS AND TESTING - A/C COMPRESSOR
CLUTCH RELAY

RELAY TEST

The compressor clutch relay (Fig. 6) is located in

the Power Distribution Center (PDC). Refer to the
PDC label for relay identification and location.
Remove the relay from the PDC to perform the fol-
lowing tests:

(1) A relay in the de-energized position should

have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 2. If not OK, replace the faulty relay.

(2) Resistance between terminals 85 and 86 (elec-

tromagnet) should be 75 ± 5 ohms. If OK, go to Step
3. If not OK, replace the faulty relay.

(3) Connect a battery to terminals 85 and 86.

There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, see Relay Circuit Test in the Diagno-
sis and Testing section of this group. If not OK,
replace the faulty relay.

RELAY CIRCUIT TEST

For circuit descriptions and diagrams, (Refer to

Appropriate Wiring Information).

(1) The relay common feed terminal cavity (30) is

connected to fused battery feed. There should be bat-
tery voltage at the cavity for relay terminal 30 at all
times. If OK, go to Step 2. If not OK, repair the open
circuit to the fuse in the PDC as required.

(2) The relay normally closed terminal (87A) is not

used in this application. Go to Step 3.

(3) The relay normally open terminal cavity (87) is

connected to the compressor clutch coil. There should
be continuity between this cavity and the A/C compres-
sor clutch relay output circuit cavity of the compressor

clutch coil wire harness connector. If OK, go to Step 4.
If not OK, repair the open circuit as required.

(4) The relay coil battery terminal (86) is connected

to the fused ignition switch output (run/start) circuit.
There should be battery voltage at the cavity for relay
terminal 86 with the ignition switch in the On posi-
tion. If OK, go to Step 5. If not OK, repair the open
circuit to the fuse in the junction block as required.

(5) The coil ground terminal cavity (85) is switched

to ground through the Powertrain Control Module
(PCM). There should be continuity between this cav-
ity and the A/C compressor clutch relay control cir-
cuit cavity of the PCM wire harness connector C
(gray) at all times. If not OK, repair the open circuit
as required.

REMOVAL

(1) Disconnect and isolate the battery negative

cable.

(2) Remove the cover from the Power Distribution

Center (PDC) (Fig. 7).

(3) Refer to the label on the PDC for compressor

clutch relay identification and location.

(4) Unplug the compressor clutch relay from the

PDC.

INSTALLATION

(1) Install the compressor clutch relay by aligning

the relay terminals with the cavities in the PDC and
pushing the relay firmly into place.

(2) Install the PDC cover.
(3) Connect the battery negative cable.
(4) Test the relay operation.

Fig. 6 A/C COMPRESSOR CLUTCH RELAY

30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED

Fig. 7 POWER DISTRIBUTION CENTER (PDC)

1 - POWER DISTRIBUTION CENTER COVER
2 - POWER DISTRIBUTION CENTER

24 - 12

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A/C COMPRESSOR CLUTCH RELAY (Continued)

A/C HEATER CONTROL

REMOVAL

WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.

(1) Open hood and disconnect the negative battery

cable remote terminal from the remote battery post.

(2) Remove the ash receiver assembly, if necessary.
(3) Remove the instrument panel center trim bezel

and remove the two electrical connectors from the
back of the control head and traction control switch
(if equipped) (Fig. 8) and (Fig. 9).

(4) From the back of the center trim bezel, remove

the six retaining screws from the a/c heater control
head and remove from the bezel.

INSTALLATION

(1) Place the control into place on the back of the

instrument panel center bezel and install the six
retaining screws to the a/c heater control.

(2) Connect the two electrical connectors to the

back of the control head and traction control switch
(if equipped).

(3) Install the instrument panel center bezel.
(4) Install the ash receiver assembly, if necessary.
(5) Connect the negative battery cable remote ter-

minal to the remote battery post.

(6) To allow the BCM to learn the new control

head, perform HVAC system calibration. (Refer to 24
- HEATING & AIR CONDITIONING - STANDARD
PROCEDURE - HVAC SYSTEM CALIBRATION)

A/C PRESSURE TRANSDUCER

REMOVAL

(1) Open hood and disconnect the negative battery

cable remote terminal from the remote battery post
(Fig. 10).

(2) Disconnect the wire harness connector from the

a/c pressure transducer.

CAUTION: A slight release of pressure trapped in
the fitting may be experienced. It is not necessary
to discharge the refrigerant system.

(3) Remove the transducer with a counterclockwise

rotation using a 14 mm open-end wrench.

Fig. 8 INSTRUMENT PANEL CENTER TRIM BEZEL

REMOVE/INSTALL

Fig. 9 A/C HEATER CONTROL REMOVE/INSTALL

1 - RETAINING SCREWS

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24 - 13

INSTALLATION

(1) Install the a/c pressure transducer on the dis-

charge line fitting and tighten to 6 N·m (50 in. lbs.).

(2) Plug in the wire harness connector to the a/c

pressure transducer.

(3) Connect the battery negative cable to the

remote battery post.

AMBIENT TEMP SENSOR

REMOVAL

The ambient air temperature sensor is located on

the inside of the right front bumper beam (Fig. 11).
This sensor will inform the ATC system of the ambi-
ent temperature outside the vehicle. This sensor is
used by the ATC system to adjust blower speed, tem-
perature offsets, evaporator temperatures and mode
control.

(1) Remove sensor mounting screw.
(2) Disconnect sensor wiring connector.

INSTALLATION

(1) Connect the sensor wiring harness connector.
(2) Install the sensor fastener screw and tighten to

2.2 N·m (20 in. lbs.).

POWER MODULE

DESCRIPTION

The blower motor power module is only used in

vehicles equipped with Automatic Temperature Con-
trol (ATC). It is located on the lower right side of the
HVAC unit housing, and is controlled by the Body
Control Module (BCM).

OPERATION

The power module receives pulse width modulated

(PWM) signals from the BCM. The power module
varies voltage to the blower motor for different
blower speeds based on the ATC software. There are
14 selectable speeds, while the Auto mode provides
256 variations.

REMOVAL

WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRECAU-
TIONS COULD RESULT IN AN ACCIDENTAL AIRBAG
DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

Fig. 10 NEGATIVE BATTERY CABLE REMOTE

TERMINAL

1 - RIGHT STRUT TOWER
2 - AIR CLEANER INLET TUBE
3 - REMOTE TERMINAL

Fig. 11 AMBIENT TEMPERATURE SENSOR

LOCATION

1 - AMBIENT TEMPERATURE SENSOR
2 - FRONT FASCIA
3 - POWER STEERING COOLER

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A/C PRESSURE TRANSDUCER (Continued)