1998 DODGE RAM 1500 hood open

(8) Install the left a-pillar trim. (Refer to 23 -
BODY/INTERIOR/A-PILLAR TRIM - INSTALLA-
TION)
(9) Position the left end cap and seat the attach-
ment clips fully.
(10) Install the right side mounting bolts on the
a-pillar and one right mounting bolt on the cowl side
panel and tighten to 12 N´m (9 ft. lbs.).
(11) Install the right a-pillar trim panel. (Refer to
23 - BODY/INTERIOR/A-PILLAR TRIM - INSTAL-
LATION)
(12) Position the right end cap and seat the
attachment clips fully.
(13) Install the one HVAC mounting screw.
(14) Connect the radio antenna.
(15) Connect the two electrical connectors at the
right cowl panel.
(16) Install the right cowl trim cover. (Refer to 23 -
BODY/INTERIOR/COWL TRIM - INSTALLATION)
(17) Connect the air bag control module electrical
connector.
(18) Install the center bracket bolts and tighten to
12 N´m (9 ft. lbs.).
(19) Install the floor console, if equipped. (Refer to
23 - BODY/INTERIOR/FLOOR CONSOLE - INSTAL-
LATION)
(20) Install the air bag control module cover, if
equipped.
(21) Connect the park brake release handle actua-
tor rod.
(22) Install the hood release handle and tighten
the screws.
(23) Install the two bolts at the column support
bracket and tighten to 14 N´m (10 ft. lbs.).
(24) Install the steering column. (Refer to 19 -
STEERING/COLUMN - INSTALLATION)
(25) Connect the wire harness electrical connectors
above the brake pedal.
(26) Install the two top instrument panel bolts and
tighten to 12 N´m (9 ft. lbs.).
(27) Install the four top instrument panel screws.
(28) Install the instrument panel top cover. (Refer
to 23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP COVER - INSTALLATION)
INSTRUMENT PANEL
HEADLAMP SWITCH BEZEL
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Using a trim stick C-4755 or equivalent,
release the top clips on the steering column opening
cover and the lower drivers side bezel.
(2) Using a trim stick C-4755 or equivalent,
release the switch bezel. (Fig. 17)
(3) Disconnect the electrical connector and remove
the bezel.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Connect the electrical connector.
Fig. 17 HEADLIGHT SWITCH BEZEL
1 - SWITCH BEZEL
2 - INSTRUMENT PANEL
3 - ELECTRICAL CONNECTOR
4 - HEADLIGHT SWITCH
23 - 56 INSTRUMENT PANELDR
INSTRUMENT PANEL ASSEMBLY (Continued)

(3) Install the storage bin, if equipped. (Refer to 23
- BODY/INSTRUMENT PANEL/STORAGE BIN -
INSTALLATION)
(4) Install the cup holder, if equipped. (Refer to 23
- BODY/INSTRUMENT PANEL/CUP HOLDER -
INSTALLATION)
(5) Install the glove box. (Refer to 23 - BODY/IN-
STRUMENT PANEL/GLOVE BOX - INSTALLA-
TION)
(6) Install the ash receiver. (Refer to 23 - BODY/
INSTRUMENT PANEL/ASH RECEIVER - INSTAL-
LATION)
(7) Install the passenger side cowl trim panel.
(Refer to 23 - BODY/INTERIOR/COWL TRIM -
INSTALLATION)
(8) Position the passenger side end cap and seat
fully.
STEERING COLUMN OPENING
COVER
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Remove the two lower screws. (Fig. 21)
(2) Using a trim stick C-4755 or equivalent,
release the upper clips and remove the cover.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURETO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Position the cover and seat the upper clips
fully.
(2) Install the two lower screws.
STEERING COLUMN OPENING
SUPPORT BRACKET
REMOVAL
(1) Remove the steering column opening cover.
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN OPENING COVER - REMOVAL)
(2) Remove the two screws and remove the diag-
nostic connector.
(3) Loosen the screws and remove the hood release
handle from the bracket.
(4) Remove the two bracket screws and slide
upward off the locating tabs to remove. (Fig. 22)
INSTALLATION
(1) Position the bracket onto the locating tabs and
slide down.
(2) Install the two screws.
(3) Install the diagnostic connector and install the
two screws.
(4) Install the hood release handle and tighten the
screws.
Fig. 21 STEERING COLUMN OPENING COVER
1 - SCREWS (2)
2 - COVER
23 - 60 INSTRUMENT PANELDR
INSTRUMENT PANEL LOWER SURROUND (Continued)

After the system has been tested for leaks and
evacuated, a refrigerant (R-134a) charge can be
injected into the system.
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) If using a separate vacuum pump close all
valves before disconnecting pump. Connect manifold
gauge set to the A/C service ports.
NOTE: Always refer to the underhood HVAC Speci-
fication label for the refrigerant fill level of the vehi-
cle being serviced.
(2) Measure refrigerant (refer to capacities). Refer
to the instructions provided with the equipment
being used.
(3) Verify engine is shut off. Open the suction and
discharge valves. Open the charge valve to allow the
refrigerant to flow into the system. When the trans-
fer of refrigerant has stopped, close the suction and
discharge valve.
(4) If all of the charge did not transfer from the
dispensing device, put vehicle controls into the fol-
lowing mode:
²Automatic transmission in park or manual
transmission in neutral
²Engine at idle
²A/C mode control set to outside air
²A/C mode control set to panel mode
²A/C temperature control set to full cool
²Blower motor control set on highest speed
²Vehicle windows closed
If the A/C compressor does not engage, test the
compressor clutch control circuit and correct any fail-
ure (Refer to 8 - ELECTRICAL/WIRING DIAGRAM
INFORMATION - DIAGNOSIS AND TESTING).
(5) Open the suction valve to allow the remaining
refrigerant to transfer to the system.
WARNING: TAKE CARE NOT TO OPEN THE DIS-
CHARGE (HIGH-PRESSURE) VALVE AT THIS TIME.
(6) Close all valves and test the A/C system perfor-
mance.
(7) Disconnect the charging station or manifold
gauge set. Install the service port caps.
REFRIGERANT CHARGE CAPACITY
The R-134a refrigerant system charge capacity for
this vehicle can be found on the underhood HVAC
specfication tag.
A/C COMPRESSOR
DESCRIPTION
DESCRIPTION - A/C COMPRESSOR
The A/C system on models equipped with the 5.9L
engine use a Sanden SD-7 reciprocating swash plate-
type compressor. This compressor has a fixed dis-
placement of 165 cubic centimeter (10.068 cubic
inches) and has both the suction and discharge ports
located on the cylinder head.
The A/C system on models equipped with the 3.7L,
4.7L and 5.7L engines use a Denso 10S17 reciprocat-
ing swash plate-type compressor. This compressor
has a fixed displacement of 170 cubic centimeter and
has both the suction and discharge ports located on
the cylinder head.
A label identifying the use of R-134a refrigerant is
located on both A/C compressors.
DESCRIPTION - HIGH PRESSURE RELIEF
VALVE
A high pressure relief valve is located on the com-
pressor cylinder head, which is on the rear of the
compressor. This mechanical valve is designed to
vent refrigerant from the system to protect against
damage to the compressor and other system compo-
nents, caused by condenser air flow restriction or an
overcharge of refrigerant.
OPERATION
OPERATION - A/C COMPRESSOR
The A/C compressor is driven by the engine
through an electric clutch, drive pulley and belt
arrangement. The compressor is lubricated by refrig-
erant oil that is circulated throughout the refrigerant
system with the refrigerant.
The compressor draws in low-pressure refrigerant
vapor from the evaporator through its suction port. It
then compresses the refrigerant into a high-pressure,
high-temperature refrigerant vapor, which is then
pumped to the condenser through the compressor dis-
charge port.
The compressor cannot be repaired. If faulty or
damaged, the entire compressor assembly must be
replaced. The compressor clutch, pulley and clutch
coil are available for service.
OPERATION - HIGH PRESSURE RELIEF VALVE
The high pressure relief valve vents the system
when a discharge pressure of 3445 to 4135 kPa (500
to 600 psi) or above is reached. The valve closes
24 - 48 PLUMBINGDR
PLUMBING (Continued)