Blower Motor Switch; Compressor - Dodge 2000 DURANGO Service Manual

DN
DIAGNOSIS AND TESTING (Continued)
(2) Unplug the wire harness connector from the
blower motor resistor.
(3) Check for continuity between each of the
blower motor switch input terminals of the resistor
and the resistor output terminal. In each case there
should be continuity. If OK, repair the wire harness
circuits between the blower motor switch and the
blower motor resistor or blower motor as required. If
not OK, replace the faulty blower motor resistor.

BLOWER MOTOR SWITCH

FRONT
For circuit descriptions and diagrams, refer to
8W-42 - Air Conditioning/Heater in Group 8W - Wir-
ing Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL,
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Check for battery voltage at the fuse in the
Power Distribution Center (PDC). If OK, go to Step
2. If not OK, repair the shorted circuit or component
as required and replace the faulty fuse.
(2) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the heater-A/C control from the instrument
panel. Check for continuity between the ground cir-
cuit cavity of the heater-A/C control wire harness
connector and a good ground. There should be conti-
nuity. If OK, go to Step 3. If not OK, repair the open
circuit to ground as required.
(3) With the heater-A/C control wire harness con-
nector unplugged, place the heater-A/C mode control
switch knob to any position except the Off position.
Check for continuity between the ground circuit ter-
minal and each of the blower motor driver circuit ter-
minals of the heater-A/C control as you move the
blower motor switch knob to each of the four speed
positions. There should be continuity at each driver
circuit terminal in only one blower motor switch
speed position. If OK, test and repair the blower
driver circuits between the heater-A/C control con-
nector and the blower motor resistor as required. If
not OK, replace the faulty heater-A/C control unit.
REAR
For circuit descriptions and diagrams, refer to
8W-42 - Air Conditioning/Heater in Group 8W - Wir-
ing Diagrams.
GROUP 8M - PASSIVE
STEERING COLUMN,
HEATING AND AIR CONDITIONING
(1) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the rear blower motor switch from the head-
liner. Check for continuity between the ground circuit
cavity of the rear blower motor switch wire harness
connector and a good ground. There should be conti-
nuity. If OK, go to Step 2. If not OK, repair the open
circuit to ground as required.
(2) With the rear blower motor switch wire har-
ness connector unplugged, place the rear blower
motor switch knob to any position except the Off
position. Check for continuity between the ground
circuit terminal and each of the blower motor driver
circuit terminals of the rear blower motor switch as
you move the blower motor switch knob to each of
the three speed positions. There should be continuity
at each driver circuit terminal in only one blower
motor switch speed position. If OK, test and repair
the rear blower driver circuits between the rear
blower motor switch wire harness connector and the
OR
blower motor resistor as required. If not OK, replace
the faulty rear blower motor switch.

COMPRESSOR

When investigating an air conditioning related
noise, you must first know the conditions under
which the noise occurs. These conditions include:
weather, vehicle speed, transmission in gear or neu-
tral, engine speed, engine temperature, and any
other special conditions. Noises that develop during
air conditioning operation can often be misleading.
For example: What sounds like a failed front bearing
or connecting rod, may be caused by loose bolts, nuts,
mounting brackets, or a loose compressor clutch
assembly.
Drive belts are speed sensitive. At different engine
speeds and depending upon belt tension, belts can
develop noises that are mistaken for a compressor
noise. Improper belt tension can cause a misleading
noise when the compressor clutch is engaged, which
may not occur when the compressor clutch is disen-
gaged. Check the serpentine drive belt condition and
tension as described in Cooling System before begin-
ning this procedure.
(1) Select a quiet area for testing. Duplicate the
complaint conditions as much as possible. Switch the
compressor on and off several times to clearly iden-
tify the compressor noise. Listen to the compressor
while the clutch is engaged and disengaged. Probe
the compressor with an engine stethoscope or a long
screwdriver with the handle held to your ear to bet-
ter localize the source of the noise.
(2) Loosen all of the compressor mounting hard-
ware and retighten. Tighten the compressor clutch
mounting nut. Be certain that the clutch coil is
mounted securely to the compressor, and that the
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