Valve DODGE RAM 1500 1998 2.G Workshop Manual
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Page 2114 of 2627

(3) Remove the screw holding the detent spring
(Fig. 135) onto the valve body.
(4) Remove the detent spring from the valve body.
(5) Remove the TRS selector plate from the valve
body and the manual valve.
(6) Remove the clutch passage seals from the valve
body, if necessary.
(7) Remove the screws holding the accumulator
cover onto the valve body (Fig. 136).
(8) Remove the accumulator springs and pistons
from the valve body. Note which accumulator piston
and spring belong in each location.
(9) Place the valve body on the bench with the
transfer plate upward.
NOTE: The valve body contains seven check balls.
The transfer plate must be placed upward to pre-
vent losing the check balls when the transfer plate
is removed from the valve body.
(10) Remove the screws holding the valve body to
the valve body transfer plate.
Fig. 135 Valve Body External Components
1 - TRS SELECTOR PLATE
2 - DETENT SPRING
3 - CLUTCH PASSAGE SEALS
Fig. 136 Valve Body Components
1 - LOW/REVERSE ACCUMULATOR 6 - OVERDRIVE ACCUMULATOR
2 - LOW/REVERSE SWITCH VALVE 7 - UNDERDRIVE ACCUMULATOR
3 - UPPER VALVE BODY 8 - 4C ACCUMULATOR
4 - MANUAL VALVE 9 - 2C ACCUMULATOR
5 - SOLENOID SWITCH VALVE
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 411
VALVE BODY (Continued)
Page 2115 of 2627

(11) Remove the transfer plate from the valve
body. Note the location of all check balls (Fig. 137).
(12) Remove the check balls from the valve body.
(13) Remove the retainers securing the solenoid
switch valve, manual valve, and the low/reverse
switch valve into the valve body and remove the
associated valve and spring. Tag each valve and
spring combination with location information to aid
in assembly. (Fig. 138)
CLEANING
Clean the valve housings, valves, plugs, springs,
and separator plates with a standard parts cleaning
solution only. Do not use gasoline, kerosene, or any
type of caustic solution. (Fig. 139)
Do not immerse any of the electrical components in
cleaning solution. Clean the electrical components by
wiping them off with dry shop towels only.
Dry all except the electrical parts with compressed
air. Make sure all passages are clean and free from
obstructions.Do not use rags or shop towels to
dry or wipe off valve body components. Lint
from these materials can stick to valve body
parts, interfere with valve operation, and clog
filters and fluid passages.
Fig. 137 Check Ball Locations
Fig. 138 Valve Body Components
1 - SOLENOID SWITCH VALVE
2 - MANUAL VALVE
3 - LOW REVERSE SWITCH VALVE
4 - LOW REVERSE ACCUMULATOR
5 - 2ND CLUTCH ACCUMULATOR
6 - UNDERDRIVE ACCUMULATOR
7 - OVERDRIVE ACCUMULATOR
8 - 4TH CLUTCH ACCUMULATOR
9 - CHECK BALLS (7)
21 - 412 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
VALVE BODY (Continued)
Page 2116 of 2627

INSPECTION
Inspect all of the valve body mating surfaces for
scratches, nicks, burrs, or distortion. Use a straight-
edge to check surface flatness. Minor scratches may
be removed with crocus cloth using only very light
pressure.
Minor distortion of a valve body mating surface
may be corrected by smoothing the surface with a
sheet of crocus cloth. Position the crocus cloth on a
surface plate, sheet of plate glass or equally flat sur-
face. If distortion is severe or any surfaces are
heavily scored, the valve body will have to be
replaced.
Inspect the valves and plugs (Fig. 140) for
scratches, burrs, nicks, or scores. Minor surface
scratches on steel valves and plugs can be removed
with crocus cloth butdo not round off the edges
of the valve or plug lands.Maintaining sharpness
of these edges is vitally important. The edges prevent
foreign matter from lodging between the valves and
plugs and the bore.Inspect all the valve and plug bores in the valve
body. Use a penlight to view the bore interiors.
Replace the valve body if any bores are distorted or
scored. Inspect all of the valve body springs. The
springs must be free of distortion, warpage or broken
coils.
Trial fit each valve and plug in its bore to check
freedom of operation. When clean and dry, the valves
and plugs should drop freely into the bores.
Valve body bores do not change dimensionally with
use. If the valve body functioned correctly when new,
it will continue to operate properly after cleaning and
inspection. It should not be necessary to replace a
valve body assembly unless it is damaged in han-
dling.
Inspect all the accumulator bores in the valve body.
Use a penlight to view the bore interiors. Replace the
valve body if any bores are distorted or scored.
Inspect all of the accumulator springs. The springs
must be free of distortion, warpage or broken coils.
Fig. 139 Valve Body Components
1 - SOLENOID SWITCH VALVE
2 - MANUAL VALVE
3 - LOW REVERSE SWITCH VALVE
4 - LOW REVERSE ACCUMULATOR
5 - 2ND CLUTCH ACCUMULATOR
6 - UNDERDRIVE ACCUMULATOR
7 - OVERDRIVE ACCUMULATOR
8 - 4TH CLUTCH ACCUMULATOR
9 - CHECK BALLS (7)
Fig. 140 Valve Body Components
1 - SOLENOID SWITCH VALVE
2 - MANUAL VALVE
3 - LOW REVERSE SWITCH VALVE
4 - LOW REVERSE ACCUMULATOR
5 - 2ND CLUTCH ACCUMULATOR
6 - UNDERDRIVE ACCUMULATOR
7 - OVERDRIVE ACCUMULATOR
8 - 4TH CLUTCH ACCUMULATOR
9 - CHECK BALLS (7)
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 413
VALVE BODY (Continued)
Page 2117 of 2627

Inspect all the fluid seals on the valve body (Fig.
141). Replace any seals that are cracked, distorted, or
damaged in any way. These seals pass fluid pressure
directly to the clutches. Any pressure leak at these
points, may cause transmission performance prob-
lems.
ASSEMBLY
(1) Lubricate valves, springs, and the housing
valve bores with clean transmission fluid.
(2) Install solenoid switch valve, manual valve,
and the low/reverse switch valve into the valve body.
(3) Install the retainers to hold each valve into the
valve body.
(4) Install the valve body check balls into their
proper locations.
(5) Position the transfer plate onto the valve body.
(6) Install the screws to hold the transfer plate to
the valve body. Tighten the screws to 5.6 N´m (50 in.
lbs.).
(7) Install the accumulator pistons and springs
into the valve body in the location from which they
were removed. Note that all accumulators except the
overdrive have two springs. The overdrive accumula-
tor piston has only one spring.
(8) Position the accumulator cover onto the valve
body.(9) Install the screws to hold the accumulator
cover onto the valve body. Tighten the screws to 8
N´m (70 in. lbs.).
(10) Install the TRS selector plate onto the valve
body and the manual valve.
(11) Install the solenoid and pressure switch
assembly onto the valve body.
(12) Install the screws to hold the solenoid and
pressure switch assembly onto the valve body.
Tighten the screws to 5.7 N´m (50 in. lbs.). Tighten
the screws adjacent to the arrows cast into the bot-
tom of the transfer plate first.
(13) Position the detent spring onto the valve body.
(14) Install the screw to hold the detent spring
onto the valve body. Tighten the screw to 4.5 N´m (40
in. lbs.).
(15) Install new clutch passage seals onto the
valve body, if necessary
INSTALLATION
(1) Check condition of seals on valve body and the
solenoid and pressure switch assembly. Replace seals
if cut or worn.
(2) Place TRS selector plate in the PARK position.
(3) Place the transmission in the PARK position.
(4) Lubricate seal on the solenoid and pressure
switch assembly connector with petroleum jelly.
(5) Position valve body in transmission and align
the manual lever on the valve body to the pin on the
transmission manual shift lever.
(6) Seat valve body in case and install one or two
bolts to hold valve body in place.
(7) Tighten valve body bolts alternately and evenly
to 12 N´m (105 in. lbs.) torque.
(8) Install a new primary oil filter seal in the oil
pump inlet bore. Seat the seal in the bore with the
butt end of a hammer, or other suitable tool.
CAUTION: The primary oil filter seal MUST be fully
installed flush against the oil pump body. DO NOT
install the seal onto the filter neck and attempt to
install the filter and seal as an assembly. Damage to
the transmission will result.
(9) Place replacement filter in position on valve
body and into the oil pump.
(10) Install screw to hold filter to valve body.
Tighten screw to 4.5 N´m (40 in. lbs.) torque.
(11) Connect the solenoid and pressure switch
assembly connector.
(12) Install oil pan. Tighten pan bolts to 12 N´m
(105 in. lbs.) torque.
(13) Lower vehicle and fill transmission with
MopartATF +4.
(14) Check and adjust gearshift cable, if necessary.
Fig. 141 Valve Body Seals
1 - UNDERDRIVE ACCUMULATOR (2 SPRINGS)
2 - 4TH CLUTCH ACCUMULATOR (2 SPRINGS)
3 - 2ND CLUTCH ACCUMULATOR (2 SPRINGS)
4 - LOW REVERSE ACCUMULATOR (2 SPRINGS)
5 - LOW/REVERSE PASSAGE SEAL
6 - 2ND CLUTCH PASSAGE SEAL
7 - 4TH CLUTCH PASSAGE SEAL
8 - OVERDRIVE ACCUMULATOR (1 SPRING)
21 - 414 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
VALVE BODY (Continued)
Page 2282 of 2627

STANDARD PROCEDURE
STANDARD PROCEDURE - TIRE ROTATION
Tires on the front and rear axles operate at differ-
ent loads and perform different steering, driving, and
braking functions. For these reasons, the tires wear
at unequal rates. They may also develop irregular
wear patterns. These effects can be reduced by rotat-
ing the tires according to the maintenance schedule
in the Owners Manual. This will improve tread life,
traction and maintain a smooth quiet ride.
The recommended method of tire rotation is (Fig.
4) & (Fig. 5). Other methods can be used, but may
not provide the same tire longevity benefits.
CAUTION: 3500 Dual rear tires have a new tire rota-
tion pattern. This is to accommodate the asymmet-
rical design of the ON/OFF road tires and the use of
the outlined white letter (OWL) tires. When replac-
ing a flat, the spare tire may have to be remounted
on the rim or installed at a different location to
maintain the correct placement of the asymmetrical
design or the (OWL).
STANDARD PROCEDURE - MATCH MOUNTING
Wheels and tires are match mounted at the factory.
This means that the high spot of the tire is matched
to the low spot on the wheel rim. Each are marked
with a bright colored temporary label on the out-
board surface for alignment. The wheel is also
marked permanently on the inside of the rim in the
tire well. This permanent mark may be a paint dot
or line, a permanent label or a stamped impression
such as an X. An optional location mark is a small
spherical indentation on the vertical face of the out-
board flange on some non styled base steel wheels.
The tire must be removed to locate the permanent
mark on the inside of the wheel.
Before dismounting a tire from its wheel, a refer-
ence mark should be placed on the tire at the valve
stem location. This reference will ensure that it is
remounted in the original position on the wheel.
(1) Remove the tire and wheel assembly from the
vehicle and mount on a service dynamic balance
machine.
(2) Measure the total runout on the center of the
tire tread rib with a dial indicator. Record the indi-
cator reading. Mark the tire to indicate the high spot.
Place a mark on the tire at the valve stem location
(Fig. 6).
Fig. 4 TIRE ROTATION PATTERN - SINGLE REAR
WHEEL (SRW)
Fig. 5 TIRE ROTATION PATTERN - DUAL REAR
WHEELS (DRW)
Fig. 6 First Measurement On Tire
1 - REFERENCE MARK
2 - 1ST MEASUREMENT HIGH SPOT MARK TIRE AND RIM
3 - WHEEL
4 - VALVE STEM
DRTIRES/WHEELS 22 - 3
TIRES/WHEELS (Continued)
Page 2283 of 2627

(3) Break down the tire and remount it 180
degrees on the rim (Fig. 7).
(4) Measure the total indicator runout again. Mark
the tire to indicate the high spot.
(5) If runout is still excessive, the following proce-
dures must be done.
²If the high spot is within 101.6 mm (4.0 in.) of
the first spot and is still excessive, replace the tire.
²If the high spot is within 101.6 mm (4.0 in.) of
the first spot on the wheel, the wheel may be out of
specifications. Refer to Wheel and Tire Runout.
²If the high spot is NOT within 101.6 mm (4.0
in.) of either high spot, draw an arrow on the tread
from second high spot to first. Break down the tire
and remount it 90 degrees on rim in that direction
(Fig. 8). This procedure will normally reduce the
runout to an acceptable amount, if not replace the
rim.
STANDARD PROCEDURE - TIRE AND WHEEL
BALANCE
It is recommended that a two plane service
dynamic balancer be used when a tire and wheel
assembly require balancing. Refer to balancer opera-
tion instructions for proper cone mounting proce-
dures. Typically use front cone mounting method for
steel wheels. For aluminum wheel use back cone
mounting method without cone spring.NOTE: Static should be used only when a two plane
balancer is not available.
NOTE: Cast aluminum and forged aluminum wheels
require coated balance weights and special align-
ment equipment.
Wheel balancing can be accomplished with either
on or off vehicle equipment. When using on-vehicle
balancing equipment, remove the opposite wheel/tire.
Off-vehicle balancing is recommended.
For static balancing, find the location of the heavy
spot causing the imbalance. Counter balance wheel
directly opposite the heavy spot. Determine weight
required to counter balance the area of imbalance.
Place half of this weight on theinnerrim flange and
the other half on theouterrim flange (Fig. 9).
For dynamic balancing, the balancing equipment is
designed to locate the amount of weight to be applied
to both the inner and outer rim flange (Fig. 10).
Fig. 7 Remount Tire 180 Degrees
1 - VALVE STEM
2 - REFERENCE MARK
Fig. 8 Remount Tire 90 Degrees In Direction of
Arrow
1 - 2ND HIGH SPOT ON TIRE
2 - 1ST HIGH SPOT ON TIRE
22 - 4 TIRES/WHEELSDR
TIRES/WHEELS (Continued)
Page 2286 of 2627

DESCRIPTION - TIRE PRESSURE FOR HIGH
SPEEDS
For proper tire pressure specification refer to the
Owners Manual.
DESCRIPTION - REPLACEMENT TIRES
The original equipment tires provide a proper bal-
ance of many characteristics such as:
²Ride
²Noise
²Handling
²Durability
²Tread life
²Traction
²Rolling resistance
²Speed capability
It is recommended that tires equivalent to the orig-
inal equipment tires be used when replacement is
needed.
Failure to use equivalent replacement tires may
adversely affect the safety and handling of the vehi-
cle.
The use of oversize tires may cause interference
with vehicle components. Under extremes of suspen-
sion and steering travel, interference with vehicle
components may cause tire damage.
WARNING: FAILURE TO EQUIP THE VEHICLE WITH
TIRES HAVING ADEQUATE SPEED CAPABILITY
CAN RESULT IN SUDDEN TIRE FAILURE.
DESCRIPTION - TIRE INFLATION PRESSURES
Under inflation will cause rapid shoulder wear, tire
flexing, and possible tire failure (Fig. 12).Over inflation will cause rapid center wear and
loss of the tire's ability to cushion shocks (Fig. 13).
Improper inflation can cause:
²Uneven wear patterns
²Reduced tread life
²Reduced fuel economy
²Unsatisfactory ride
²Vehicle drift
For proper tire pressure specification refer to the
vehicles Owners Manual.
WARNING: OVER OR UNDER INFLATED TIRES CAN
AFFECT VEHICLE HANDLING AND TREAD WEAR.
THIS MAY CAUSE THE TIRE TO FAIL SUDDENLY,
RESULTING IN LOSS OF VEHICLE CONTROL.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - PRESSURE
GAUGES
A quality air pressure gauge is recommended to
check tire pressure. After checking the air pressure,
replace valve cap finger tight.
DIAGNOSIS AND TESTING - TIRE NOISE OR
VIBRATION
Radial-ply tires are sensitive to force impulses
caused by improper mounting, vibration, wheel
defects, or possibly tire imbalance.
To find out if tires are causing the noise or vibra-
tion, drive the vehicle over a smooth road at varying
speeds. Note the noise level during acceleration and
deceleration. The engine, differential and exhaust
noises will change as speed varies, while the tire
noise will usually remain constant.
Fig. 12 Under Inflation Wear
1 - THIN TIRE THREAD AREAS
Fig. 13 Over Inflation Wear
1 - THIN TIRE THREAD AREA
DRTIRES/WHEELS 22 - 7
TIRES (Continued)
Page 2290 of 2627

WHEELS
DESCRIPTION
Original equipment wheels are designed for the
specified Maximum Vehicle Capacity.
All models use steel or aluminum drop center
wheels.
Aluminum wheels require special balance weights
and alignment equipment.
(1) On vehicles equipped with dual rear wheels,
The rim is an eight stud hole pattern wheel. The
wheels have a flat mounting surface (Fig. 18). The
slots in the wheel must be aligned to provide access
to the valve stem (Fig. 19).
OPERATION
The wheel (Fig. 20) has raised sections between
the rim flanges and the rim well. Initial inflation of
the tire forces the bead over these raised sections. In
case of tire failure, the raised sections hold the tire
in position on the wheel until the vehicle can be
brought to a safe stop.
DIAGNOSIS AND TESTING
WHEEL INSPECTION
Inspect wheels for:
²Excessive run out
²Dents or cracks
²Damaged wheel lug nut holes
²Air Leaks from any area or surface of the rim
NOTE: Do not attempt to repair a wheel by hammer-
ing, heating or welding.
If a wheel is damaged an original equipment
replacement wheel should be used. When obtaining
replacement wheels, they should be equivalent in
load carrying capacity. The diameter, width, offset,
pilot hole and bolt circle of the wheel should be the
same as the original wheel.
WARNING: FAILURE TO USE EQUIVALENT
REPLACEMENT WHEELS MAY ADVERSELY
AFFECT THE SAFETY AND HANDLING OF THE
VEHICLE. USED WHEELS ARE NOT RECOM-
MENDED. THE SERVICE HISTORY OF THE WHEEL
MAY HAVE INCLUDED SEVERE TREATMENT OR
VERY HIGH MILEAGE. THE RIM COULD FAIL WITH-
OUT WARNING.
Fig. 18 FLAT FACE WHEEL
1 - FLAT FACE
2 - VALVE STEM
Fig. 19 DUAL REAR WHEELS
1 - WINDOW OPENINGS (5)
2 - INBOARD VALVE STEM
3 - OUTBOARD VALVE STEM
Fig. 20 Safety Rim
1 - FLANGE
2 - RIDGE
3 - WELL
DRTIRES/WHEELS 22 - 11
Page 2293 of 2627

STUDS
REMOVAL
(1) Raise and support the vehicle.
(2) Remove the wheel and tire assembly.
(3) Remove the brake caliper, caliper adapter and
rotor, (Refer to 5 - BRAKES/HYDRAULIC/MECHAN-
ICAL/ROTORS - REMOVAL).
(4) Remove the stud from the hub with Remover
C-4150A (Fig. 25).
INSTALLATION
(1) Install the new stud into the hub flange.
(2) Install the three washers onto the stud, then
install the lug nut with the flat side of the nut
against the washers.
(3) Tighten the lug nut until the stud is pulled
into the hub flange. Verify that the stud is properly
seated into the flange.
(4) Remove the lug nut and washers.
(5) Install the brake rotor, caliper adapter, and cal-
iper, (Refer to 5 - BRAKES/HYDRAULIC/MECHAN-
ICAL/ROTORS - INSTALLATION).
(6) Install the wheel and tire assembly, (Refer to
22 - TIRES/WHEELS/WHEELS - STANDARD PRO-
CEDURE), use new the lug nut on stud or studs that
were replaced.
(7) Remove the support and lower vehicle.
WHEEL COVER
REMOVAL
NOTE: The hub caps must be removed before rais-
ing the vehicle off the ground.NOTE: You must use the flat end of the hub/cap
remover/installer combination tool to pry off the
wheel skins. Insert the flat tip completely and using
a back and forth motion, loosen the wheel skin.
repeat this procedure around the tire until the wheel
skin pops off.
(1) On 2500/3500 single rear wheel (SRW) models,
insert a hub/cap remover/installer combination tool
using the blade on the end of the tool to pry the cap
off in a back and forth motion.
(2) On 3500 models with dual rear wheels (DRW),
you must first remove the hub caps. The hub/cap
remover/installer combination tool must be inserted
in the pry off notch of the rear hub caps.
(3) Position the hub/cap remover/installer combina-
tion tool and pull out on the tool firmly. The cap
should come off.
(4) The wheel skins can now be removed from the
wheel.
(5) On 3500 models front hub caps use the hub/cap
remover/installer combination tool to pry off the cap
in a back and forth motion. The wheel skins can now
be removed.
INSTALLATION
INSTALLATION - REAR
(1) Install one 1 1/2 in. valve stem extension on
each rear inner wheel.
NOTE: A 3/8 in. drive 10mm deep wheel socket with
a 10 in. or greater extension can be used to remove
the existing valve stem cap and install the exten-
sion.
(2) Install one 1 in. valve stem extension on each
outer wheel.
(3) Align the cooling windows of the wheel skin
with the cooling windows of the wheel. Seat one side
of the wheel skin's retainer onto the wheel. Using a
rubber mallet, strike thew wheel skin on the outer
circumference. Strike at several locations around the
circumference until the skin is fully seated.
NOTE: The wheel skin and the hub cap are fully
seated when there is a consistent gap between the
skin/cap and the wheel.
(4) Tug on the hub/cap wheel skin to ensure that
they are properly installed.
INSTALLATION - FRONT
(1) Align the valve stem with the notch in the
wheel skin.
Fig. 25 Wheel Stud Removal
1 - REMOVER
2 - WHEEL STUD
22 - 14 TIRES/WHEELSDR
Page 2490 of 2627

The panel outlets receive airflow from the HVAC
housing through a molded plastic main panel duct,
center panel duct and two end panel ducts. The two
end panel ducts direct airflow to the left and right
instrument panel outlets, while the center panel duct
directs airflow to the two center panel outlets. Each
of these outlets can be individually adjusted to direct
the flow of air.
The floor outlets receive airflow from the HVAC
housing through the floor distribution duct. The front
floor outlets are integral to the molded plastic floor
distribution duct, which is secured to the bottom of
the housing. The floor outlets cannot be adjusted.
The air conditioner for all models is designed for
the use of non-CFC, R-134a refrigerant. The air con-
ditioning system has an evaporator to cool and dehu-
midify the incoming air prior to blending it with the
heated air. This air conditioning system uses a fixed
orifice tube in the liquid line near the condenser out-
let tube to meter refrigerant flow to the evaporator
coil. To maintain minimum evaporator temperature
and prevent evaporator freezing, a evaporator tem-
perature sensor is used. The JTEC control module is
programmed to respond to the evaporator tempera-
ture sensor input by cycling the air conditioning com-
pressor clutch as necessary to optimize air
conditioning system performance and to protect the
system from evaporator freezing.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - A/C
PERFORMANCE
The air conditioning system is designed to remove
heat and humidity from the air entering the passen-
ger compartment. The evaporator, located in the
HVAC housing, is cooled to temperatures near the
freezing point. As warm damp air passes over the
fins in the evaporator, moisture in the air condenses
to water, dehumidifying the air. Condensation on the
evaporator fins reduces the evaporators ability to
absorb heat. During periods of high heat and humid-
ity, an air conditioning system will be less effective.
With the instrument control set to Recirculation
mode, only air from the passenger compartment
passes through the evaporator. As the passenger com-
partment air dehumidifies, A/C performance levels
rise.
Humidity has an important bearing on the temper-
ature of the air delivered to the interior of the vehi-
cle. It is important to understand the effect that
humidity has on the performance of the air condition-
ing system. When humidity is high, the evaporator
has to perform a double duty. It must lower the air
temperature, and it must lower the temperature ofthe moisture in the air that condenses on the evapo-
rator fins. Condensing the moisture in the air trans-
fers heat energy into the evaporator fins and tubing.
This reduces the amount of heat the evaporator can
absorb from the air. High humidity greatly reduces
the ability of the evaporator to lower the temperature
of the air.
However, evaporator capacity used to reduce the
amount of moisture in the air is not wasted. Wring-
ing some of the moisture out of the air entering the
vehicle adds to the comfort of the passengers.
Although, an owner may expect too much from their
air conditioning system on humid days. A perfor-
mance test is the best way to determine whether the
system is performing up to standard. This test also
provides valuable clues as to the possible cause of
trouble with the air conditioning system.
PERFORMANCE TEST PROCEDURE
Review Safety Warnings and Cautions before per-
forming this procedure (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - WARNING) and
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION). Air temperature in test
room and on vehicle must be 21É C (70É F) minimum
for this test.
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) Connect a tachometer and a manifold gauge set
or A/C recycling/charging station.
(2) Set the A/C-heater mode control in the Recircu-
lation Mode position, the temperature control knob in
the full cool position, and the blower motor switch to
the highest speed position.
(3) Start the engine and hold at 1,000 rpm with
the A/C compressor clutch engaged.
(4) The engine should be warmed up to operating
temperature with the doors closed and windows
open.
(5) Insert a thermometer in the driver side center
panel A/C-heater outlet and operate the engine for
five minutes.
(6) The compressor clutch may cycle, depending
upon the ambient temperature and humidity.
(7) With the compressor clutch engaged, record the
discharge air temperature and the compressor dis-
charge pressure.
(8) If the discharge air temperature fails to meet
the specifications in the A/C Performance Tempera-
ture chart, refer to the Pressure Diagnosis chart.
DRHEATING & AIR CONDITIONING 24 - 3
HEATING & AIR CONDITIONING (Continued)