ECO mode CHEVROLET DYNASTY 1993 Manual Online
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ing seat will give a false end play reading while
gauging for proper shims. Improperly seated bearing
cups and cones are subject to low mileage failure.(2) Bearing cups and cones should be replaced if they
show signs of pitting or heat distress. If distress is seen
on either the cup or bearing rollers, both cup and cone
must be replaced. (3) Bearing preload and drag torque specifications
must be maintained to avoid premature bearing
failures. Used (original) bearing may lose up to 50% of
the original drag torque after break in. All bearing
adjustments must be made with no other compo-
nent interference or gear intermesh. (4) Replace bearings as a pair. For example, if one
differential bearing is defective, replace both differen-
tial bearings. If one input shaft bearing is defective,
replace both input shaft bearings. (5) Bearing cones must notbe reused if removed.
(6) Turning torque readings should be obtained
while smoothly rotating in either direction (break-
away reading is not indicative of the true turning
torque). (7) Replace oil baffle, if damaged.
INPUT SHAFT BEARING END PLAY ADJUST-MENT
(1) Using Tool C-4656 with Handle C-4171, press
input shaft front bearing cup slightly forward in case.
Then, using Tool C-4655 with Handle C-4171, press
bearing cup back into case from the front. Properly
position bearing cup, before checking input shaft end
play (see input shaft front bearing cup replace in
Subassembly Recondition section).This step is
not necessary if Tool C-4655 was previously used
to install input shaft front bearing cup in the
case. Also no input shaft shim has been installed
since pressing cup into case. (2) Select a gauging shim which will give 0.025 to
0.254mm (.001 to .010 inch) end play. SUGGESTION:
Measure original shim from input shaft seal retainer and select a shim 0.254mm (.010
inch) thinner than original for the gauging shim.
(3) Install gauging shim on bearing cup and install
input shaft seal retainer.
CAUTION: The input shaft seal retainer is used to
draw the input shaft front bearing cup the proper
distance into the case bore during this step. Alter-
nately tighten input shaft seal retainer bolts until
input shaft seal retainer is bottomed against case.
Tighten bolts to 28 N Im (21 ft. lbs.).
(4) Oil input shaft bearings with SAE 5W-30 engine
oil and install input shaft in case. Install bearing
retainer plate with input shaft rear bearing cup
pressed in and bearing support plate installed. Tighten
all bolts and nuts to 28 N Im (21 ft. lbs.).
(5) Position dial indicator to check input shaft end
play. Apply moderate load, by hand, to input shaft
splines (Fig. 1). Push toward rear while rotating input
shaft back and forth a number of times to settle out
bearings. Zero dial indicator. Pull input shaft toward
the front while rotating input shaft back and forth a
number of times to settle out bearings. Record end play.
(6) The shim required for proper bearing end play is
the total of the gauging shim thickness, plus end play,
minus (constant) end play of 0.051mm (.002 inch).
Combine shims, if necessary, to obtain a shim within
.04mm (.0016 inch) of the required shim (see Shim
Chart for proper shim). (7) Remove input shaft seal retainer and gauging
shim. Install shim(s) selected in step (6). Then reinstall
input shaft seal retainer with a 1/16 inch bead of
MOPAR tGasket Maker, Loctite, or equivalent for a
gasket. Record end play. Observe the CAUTIONin
step (3). Tighten input shaft seal retainer bolts to 28
N Im (21 ft. lbs.).
Fig. 14 Checking Side Gear End Play
Fig. 1 Checking Input Shaft Bearing End Play to De-
termine Shim Thickness
21 - 32 TRANSAXLE Ä
Page 1995 of 2438

THREE SPEED TORQUEFLITE AUTOMATIC TRANSAXLE INDEX
page page
Accumulator-Recondition ................... 67
Aluminum Thread Repair ................... 48
Assembly Subassembly Installation ........... 57
Band Adjustment ......................... 47
Bearing Adjustment Procedures .............. 81
Clutch and Servo Air Pressure Tests .......... 43
Differential Repair ........................ 76
Disassembly Subassembly Removal .......... 50
Fluid and Filter Change .................... 40
Fluid Drain and Refill ..................... 40
Fluid Leakage-Transaxle Torque Converter Housing Area .......................... 44
Fluid Level and Condition .................. 40
Front Clutch-Recondition ................... 62
Front Planetary & Annulus Gear-Recondition .... 65
Gearshift Linkage Adjustment ............... 46
General Information ....................... 35
Governor ............................... 48
Hydraulic Control Pressure Adjustments ....... 47
Hydraulic Pressure Tests ................... 42
Kickdown Servo (Controlled Load)-Recondition . . 67 Low/Reverse Servo-Recondition
.............. 66
Oil Cooler Flow Check .................... 48
Oil Coolers and Tubes Reverse Flushing ...... 48
Oil Pump-Recondition ..................... 62
Output Shaft Repair ...................... 71
Park/Neutral Position and Back-Up Lamp Switch . 47
Parking Pawl ............................ 71
Pump Oil Seal-Replacement ................ 61
Rear Clutch-Recondition ................... 64
Road Test .............................. 40
Selection of Lubricant ..................... 40
Special Additives ......................... 40
Three Speed Torqueflite General Diagnosis ..... 36
Throttle Pressure Linkage Adjustment ......... 46
Torque Converter Clutch Solenoid Wiring Connector ............................ 40
Transaxle and Torque Converter Removal ...... 48
Transfer Shaft Repair ..................... 68
Valve Body-Recondition .................... 57
Vehicle Speed Sensor Pinion Gear ........... 47
GENERAL INFORMATION
Safety goggles should be worn at all times
when working on these transaxles. This transaxle combines a fully automatic 3 speed
transmission, final drive gearing, and differential into
a front wheel drive system. The unit is a Metric
design. The identification markings and usage of the
transaxle are charted in Diagnosis and Tests. Transaxle operation requirements are differ-
ent for each vehicle and engine combination and
some internal parts will be different to provide
for this. Therefore, when replacing parts, refer to
the seven digit part number stamped on rear of
the transaxle oil pan flange. Within this transaxle, there are 3 primary areas:
(1) Main center line plus valve body.
(2) Transfer shaft center line (includes governor and
parking sprag). (3) Differential center line. Center distances be-
tween the main rotating parts in these 3 areas are held
precise. This maintains a low noise level through
smooth accurate mesh of the gears. The torque converter, transaxle area, and differential
are housed in an integral aluminum die casting. The
differential oil sump is common with thetransaxle
sump. Separate filling of the differential is NOT nec-
essary. The torque converter is attached to the crankshaft
through a flexible driving plate. Cooling of the con-
verter is accomplished by circulating the transaxle
fluid through an oil-to-water type cooler located in the
radiator side tank and/or an oil-to air heat ex- changer. The torque converter assembly is a sealed
unit that cannot be disassembled.
The transaxle fluid is filtered by an internal filter
attached to the lower side of the valve body assem-
bly. Engine torque is transmitted to the torque con-
verter then, through the input shaft to multiple-disc
clutches in the transaxle. The power flow depends on
the application of the clutches and bands. Refer to
Elements in Use Chart in Diagnosis and Tests sec-
tion. The transaxle consists of two multiple-disc
clutches, an overrunning clutch, two servos, a hy-
draulic accumulator, two bands, and two planetary
gear sets. They provide three forward ratios and a re-
verse ratio. The common sun gear of the planetary
gear sets is connected to the front clutch by a driving
shell. The drive shell is splined to the sun gear and
to the front clutch retainer. The hydraulic system
consists of an oil pump, and a single valve body
which contains all of the valves except the governor
valves. The transaxle sump and differential sump are
both vented through the dipstick.Output torque
from the main center line is delivered through heli-
cal gears to the transfer shaft.This gear set is a
factor of the final drive (axle) ratio. The shaft also
carries the governor and parking sprag. An integral
helical gear on the transfer shaft drives the differen-
tial ring gear. The final drive gearing is completed
with one of three gear sets producing overall top gear
ratios of 2.78, 3.02, or 3.22 depending on model and
application.
Ä TRANSAXLE 21 - 35
Page 2047 of 2438

OPERATION
The 41TE transaxle provides forward ratios of 2.84,
1.57, 1.00, and 0.69 with torque converter clutch
available in 2nd, direct, or overdrive gear; the Re-
verse ratio is 2.21. The shift lever is conventional
with six positions: P, R, N, OD, 3, and L. When OD
is selected the transaxle shifts normally through all
four speeds with torque converter clutch available in
overdrive; this position is recommended for most
driving. The 3 position is tailored for use in hilly or
mountainous driving. When 3 is selected, the trans-
mission uses only 1st, 2nd, and direct gears with
2nd-direct shift delayed to 40 mph or greater. When
operating in 3 or L positions torque converter clutch
application occurs in direct gear for improved trans-
mission cooling under heavy loads. If high engine
coolant temperature occurs, the torque converter
clutch will also engage in 2nd gear. The L position
provides maximum engine braking for descending
steep grades. Unlike most current transaxles, up-
shifts are provided to 2nd or direct gear at peak en-
gine speeds if the accelerator is depressed. This
provides engine over-speed protection and maximum
performance.
CLUTCH AND GEAR
The transaxle consists of:
² Three multiple disc input clutches
² Two multiple disc grounded clutches
² Four hydraulic accumulators
² Two planetary gear sets
This provides four forward ratios and a reverse ra-
tio. The clutch-apply pistons were designed with cen-
trifugally balanced oil cavities so that quick response
and good control can be achieved at any speed. A
push/pull piston is incorporated for two of the three
input clutches.
CAUTION: Some clutch packs appear similar, but
they are not the same. Do not interchange clutch
components as they might fail.
HYDRAULICS
The hydraulics of the transaxle provide the manual
shift lever select function, main line pressure regula-
tion, and torque converter and cooler flow control.
Oil flow to the friction elements is controlled directly
by four solenoid valves. The hydraulics also include a
unique logic-controlled ``solenoid torque converter
clutch control valve''. This valve locks out the 1st
gear reaction element with the application of 2nd, di-
rect, or overdrive gear elements. It also redirects the
1st gear solenoid output so that it can control torque
converter clutch operation. To regain access to 1st
gear, a special sequence of solenoid commands must
be used to unlock and move the solenoid torque con-
verter clutch control valve. This precludes any appli- cation of the 1st gear reaction element with other
elements applied. It also allows one solenoid to con-
trol two friction elements.
Small, high-rate accumulators are provided in each
controlled friction element circuit. These serve to ab-
sorb the pressure responses, and allow the controls to
read and respond to changes that are occurring.
SOLENOIDS
Since the solenoid valves perform virtually all con-
trol functions, these valves must be extremely dura-
ble and tolerant of normal dirt particles. For that
reason hardened-steel poppet and ball valves are
used. These are free from any close operating clear-
ances, and the solenoids operate the valves directly
without any intermediate element. Direct operation
means that these units must have very high output
so that they can close against the sizeable flow areas
and high line pressures. Fast response is also re-
quired to meet the control requirements. Two of the solenoids are normally-venting and two
are normally-applying; this was done to provide a de-
fault mode of operation. With no electrical power, the
transmission provides 2nd gear in OD, 3,orLshift
lever positions. All other transmission lever positions
will operate normally. The choice of 2nd gear was
made to provide adequate breakaway performance
while still accommodating highway speeds.
SENSORS
There are three pressure switches to identify sole-
noid application and two speed sensors to read input
(torque converter turbine) and output (parking sprag)
speeds. There is also a position switch to indicate the
manual shift lever position. The pressure switches
are incorporated in an assembly with the solenoids.
Engine speed, throttle position, temperature, etc., are
also observed. Some of these signals are read directly
from the engine control sensors; others are read from
a multiplex circuit with the powertrain control mod-
ule.
ELECTRONICS
The 41TE transmission control module is located
underhood in a potted, die-cast aluminum housing
with a sealed, 60-way connector.
ELECTRONIC MODULATED CONVERTER CLUTCH (EMCC)
The EMCC enables the torque converter clutch to
partially engage between 23 to 47 MPH before full
engagement at about 50 MPH and beyond. This fea-
ture is on all vehicles equipped with the 41TE tran-
saxle.
ADAPTIVE CONTROLS
These controls function by reading the input and
output speeds over 140 times a second and respond-
Ä TRANSAXLE 21 - 87
Page 2106 of 2438

² Park
² Neutral
² Reverse
² Second Gear
No upshifts or downshifts are allowed while in the
Limp-in mode. The position of the manual valve
alone allows the three ranges that are available. Although engine performance will be reduced while
in this mode, the vehicle can be driven in for service.
DRB II SCAN TOOL
The DRB II scan tool is a diagnostic read-out box
designed by Chrysler to gain access to the on-board
diagnostics. These on-board diagnostics are found on
all Chrysler-built cars and trucks. The DRB II scan tool has a few diagnostic capabil-
ities by itself. To perform most diagnostic tests, a
program cartridge must be inserted. It contains the
diagnostic test programs. There are scan tools available from other manufac-
tures that can be used on Chrysler vehicles. How-
ever, the diagnostic test procedures in this manual
have been designed for use with the Chrysler's DRB
II scan tool. The DRB II scan tool operates by communicating
with the module of the vehicle system being tested.
To communicate with the transmission control mod-
ule, the DRB II scan tool must be connected to the blue CCD bus connector located under the instru-
ment panel. Refer to the ``Using the DRB II Scan
Tool'' manual or the Diagnostic Procedures Manual
for information on how to use the DRB II scan tool.
DIAGNOSTIC TROUBLE CODE CHARTS
Below is a brief description of what each section of
the diagnostic trouble code charts are addressing.
² DIAGNOSTIC TROUBLE CODE- Tells the code
number and name (as shown on the DRB II scan
tool).
² BACKGROUND- A brief description of the circuit
that the transmission control module is monitoring.
² WHEN CHECKED- The point of time or condition
when the transmission control module makes it's sys-
tem check.
² ARMING CONDITIONS- The parameters that
must be met before a code can be set.
² FAULT CONDITION- What the transmission con-
trol module saw that is determined to be a problem.
(ie. voltage to high or low, switch/solenoid problems)
² FAULT SET TIME- Refers to the amount of time
(in seconds) a failure must occur before a diagnostic
trouble code is set in memory.
² EFFECT- Refers to how the fault effects transaxle
operations.
² POSSIBLE CAUSE- Refers to the systems or cir-
cuits which could cause the fault to be recorded.
21 - 146 TRANSAXLE Ä
Page 2149 of 2438

WHEELSÐTIRES
CONTENTS
page page
SPECIFICATIONS ........................ 8
TIRE SERVICE PROCEDURES .............. 1 WHEELS SERVICE PROCEDURES
........... 6
TIRE SERVICE PROCEDURES INDEX
page page
Cleaning of Tires .......................... 1
General Information ........................ 1
Pressure Gauges ......................... 2
Radial-Ply Tires ........................... 1
Repairing Leaks .......................... 3
Rotation ................................ 3 Spare TireÐCompact
...................... 1
Tire Inflation Pressures ..................... 2
Tire Noise or Vibration ..................... 3
Tire Wear Patterns ........................ 3
Tread Wear Indicators ...................... 3
GENERAL INFORMATION
Throughout this group, references may be made to a
particular vehicle by letter or number designation. A
chart showing the breakdown of these designations is
included in the Introduction Section. Tires are designed for the vehicle and provide the
best overall performance for normal operation. The
ride and handling characteristics match the vehicle's
requirements. With proper care they will give excellent
reliability traction, skid resistance and tread life. They
have load carrying capacity, when properly inflated, to
operate at loads up to the specified Maximum Vehicle
Capacity. Driving habits have more effect on tire life than any
other factor. Careful drivers will obtain, in most cases,
much greater mileage than severe or careless drivers. A
few of the driving habits which will shorten the life of
any tire are:
² Rapid acceleration and deceleration
² Severe application of brakes
² High-speed driving
² Taking turns at excessive speeds
² Striking curbs and other obstacles
Radial ply tires can be more susceptible to irregular
tread wear. It is very important to follow the tire
rotation interval shown in the section on Tire
Rotation to achieve a greater tread life potential.
RADIAL-PLY TIRES
Radial-ply tires improve handling, tread life, and
ride quality and decrease rolling resistance. Radial-ply tires must always be used in sets of four
and under no circumstances should they be used on
the front only. However, they may be mixed with temporary spare tires when necessary,
but reduced speeds are recommended. Radial-ply tires have the same load carrying capac-
ity as other types of tires of the same size. They also
use the same recommended inflation pressures.
SPARE TIREÐCOMPACT
The compact spare tire is designed for emergency
use only. The original tire should be repaired and re-
installed at the first opportunity. Refer to Owner's
Manual for complete details.
TIRE CHAINS
Tire snow chains may be used on certainmodels.
Refer to Owner's Manual for more information.
CLEANING OF TIRES
Remove protective coating on tires before delivery
of vehicle, otherwise it could cause deterioration of
tires. Remove protective coating by applying warm wa-
ter, letting it soak one minute, and then scrubbing
the coating away with a soft bristle brush. Steam cleaning may also be used for cleaning.
DO NOT use gasoline or wire brush for cleaning.
DO NOT use mineral oil or an oil-based solvent.
Ä WHEELSÐTIRES 22 - 1
Page 2154 of 2438

WHEELS SERVICE PROCEDURES INDEX
page page
General Information ........................ 6
Tire and Wheel Balance .................... 6
Tire and Wheel Run Out .................... 7 Wheel Installation
......................... 6
Wheel Replacement ....................... 6
GENERAL INFORMATION
Original equipment wheels are designed for proper
operation at all loads up to the maximum vehicle ca-
pacity. All models use steel or cast aluminum drop center
wheels. The safety rim wheel (Fig. 1) has raised sec-
tions between the rim flanges and the rim well A.
Initial inflation of the tires forces the bead over
these raised sections. In case of tire failure the raised
sections help hold the tire in position on the wheel
until the vehicle can be brought to a safe stop. Cast aluminum wheels require special balance
weights and alignment equipment.
WHEEL INSTALLATION
The wheel studs and nuts are designed for specific
applications and must be replaced with equivalent
parts. Do not use replacement parts of lessor quality
or a substitute design. All aluminum and some steel
wheels have wheel stud nuts which feature an en-
larged nose. This enlarged nose is necessary to en-
sure proper retention of the aluminum wheels. Before installing the wheel, be sure to remove any
build up of corrosion on the wheel mounting surfaces
with scraping and wire brushing. Installing wheels
without good metal-to-metal contact could cause later
loosening of wheel nuts. This could adversely affect
the safety and handling of your vehicle. To install the wheel, position it properly on the
mounting surface using the hub pilot as a guide. All wheel nuts should be lightly tightened before progres-
sively tightening them in sequence (Fig. 2). Tighten
wheel nuts to 129 N Im (95 ft. lbs.). Never use oil or
grease on studs or nuts.
WHEEL REPLACEMENT
Wheels must be replaced if they:
² have excessive run out
² are bent or dented
² leak air through welds
² have damaged bolt holes
Wheel repairs employing hammering, heating, or
welding are not allowed. Original equipment replacement wheels are avail-
able through your dealer. When obtaining wheels from
any other source, the replacement wheels should be
equivalent in load carrying capacity. The wheel dimen-
sions (diameter, width, offset, and mounting configura-
tion) must match original equipment wheels. Failure to
use equivalent replacement wheels may adversely af-
fect the safety and handling of your vehicle. Replace-
ment with used wheels is not recommended as
their service history may have included severe
treatment or very high mileage and they could
fail without warning.
TIRE AND WHEEL BALANCE
Balancing need is indicated by vibration of seats,
floor pan, or steering wheel when driving over 90 km/h
(55 mph) on a smooth road.
Fig. 1 Safety Rim
Fig. 2 Tightening Wheel Nuts (5-Stud)
22 - 6 WHEELSÐTIRES Ä
Page 2306 of 2438

is done by adjusting the blend-air door with the
TEMP control on the instrument panel. The air flow
can then be directed from the PANEL, BI-LEVEL
(panel and floor), and FLOOR-DEFROST outlets. Air
flow velocity can be adjusted with the blower speed
selector switch on the instrument panel (Fig. 6). On air conditioned vehicles, ambient air intake can
be shut off by closing the recirculating air door. This
will recirculate the air that is already inside the ve-
hicle. This is done by moving the TEMP control into
the RECIRC position. Depressing the DEFROST or
A/C button will engage the compressor. This will send refrigerant through the evaporator, and will re-
move heat and humidity from the air before it is di-
rected through or around the heater core.
SIDE WINDOW DEMISTERS
The side window demisters direct air from the
heater assembly. The outlets are located on the top
outboard corners of the instrument panel. The De-
misters operate when the A/C control mode selector
is on FLOOR or DEFROST setting.
ENGINE COOLING SYSTEM REQUIREMENTS
To maintain the performance level of the heating/
air conditioning system, the engine cooling system
must be prepared as shown in this manual. The use of a bug screen is not recommended. Any
obstructions in front of the radiator or condenser can
reduce the performance of the A/C or engine cooling
system.
Fig. 2 Fixed Displacement CompressorÐModel TR105
Fig. 3 Fixed Displacement CompressorÐModelSD709P
Fig. 4 Variable Displacement CompressorÐModel 6C17
Fig. 5 Common Blend-Air Heater A/C System
24 - 2 HEATING AND AIR CONDITIONING Ä
Page 2321 of 2438

(2) The appropriate Powertrain Diagnostic Proce-
dures Manual for diagnostic information. (3) The Compressor Clutch DiagnosisÐVariable
Displacement Compressor chart in this section. (4) On 2.2 L Turbo III engines, check for battery
voltage at the Thermal Limiter Switch located on the
compressor. If voltage is found at the cut-off and/or thermal
limiter switch, reconnect switch. Then check for bat-
tery voltage between the compressor clutch connector
terminals. If voltage is detected, perform A/C Clutch Coil
Tests. Refer to Clutch Coil Tests in this section.
CLUTCH COIL TESTS
(1) Verify battery state of charge. (Test indicator
in battery should be green). (2) Connect an ammeter (0-10 ampere scale) in se-
ries with the clutch coil terminal. Use a volt meter
(0-20 volt scale) with clip leads measuring voltage
across the battery and A/C clutch. (3) With A/C control in A/C mode and blower at
low speed, start the engine and run at normal idle. (4) The A/C clutch should engage immediately and
the clutch voltage should be within two volts of the
battery voltage. If the A/C clutch does not engage,
test the fusible link. (5) The A/C clutch coil is acceptable if the current
draw is 2.0 to 3.7 amperes at 11.5-12.5 volts at clutch
coil. This is with the work area temperature at 21ÉC
(70ÉF). If voltage is more than 12.5 volts, add electri-
cal loads by turning on electrical accessories until
voltage reads below 12.5 volts. If coil current reads zero, the coil is open and
should be replaced. If the ammeter reading is 4 am-
peres or more, the coil is shorted and should be re-
placed. If the coil voltage is not within two volts of
the battery voltage, test clutch coil feed circuit for
excessive voltage drop.
COMPRESSOR
The A/C compressor may be removed and posi-
tioned without discharging the refrigerant system.
Discharging is not necessary if removing the A/C
compressor clutch/coil assembly, engine, cylinder
head, or generator.
WARNING: REFRIGERANT PRESSURES REMAIN HIGH
EVEN THOUGH THE ENGINE MAY BE TURNED OFF.
BEFORE REMOVING A FULLY CHARGED COMPRES-
SOR, REVIEW THE SAFETY PRECAUTIONS AND
WARNINGS SECTION IN THIS GROUP. DO NOT TWIST
OR KINK THE REFRIGERANT LINES WHEN REMOV-
ING A FULLY CHARGED COMPRESSOR. SAFETY
GLASSES MUST BE WORN.
REMOVAL AND INSTALLATION
(1) Disconnect NEGATIVE battery cable.
(2) Loosen and remove drive belts (Refer to Group
7, Cooling System) and disconnect compressor clutch
wire lead. (3) Remove refrigerant lines from compressor (if
necessary). (4) Remove compressor attaching nuts and bolts
(Fig. 2 or 3).
(5) Remove compressor. If refrigerant lines were
not removed, lift compressor/clutch assembly and tie
it to a suitable component. To install, reverse the preceding operation.
Fig. 2 A/C Compressor Removal and InstallationÐ3.3L Engines
Fig. 3 A/C Compressor Removal and InstallationÐ3.0 L Engine
Ä HEATING AND AIR CONDITIONING 24 - 17
Page 2325 of 2438

(5) Evacuate and charge the refrigerant system. If
oil loss of 3 ml (1 oz) or greater is suspected, refer to
Oil Level in the Refrigerant Service Procedures sec-
tion.
COMPRESSOR HIGH PRESSURE CUT-OUT SWITCH
The High Pressure Cut Out (HPCO) switch is lo-
cated on the rear cover of the Variable Displacement
Compressor (Fig. 6). The function of the switch is to disengage the compressor clutch by monitoring the
compressor discharge (high) pressure. The HPCO
Switch is in the same circuit as the Differential Pres-
sure Cut Out (DPCO) switch and Ambient Switch.
DIAGNOSIS
Review Safety Precautions and Warnings before
proceeding with this operation. Connect a suitable manifold gauge set to the refrig-
erant system service ports. Work area temperature
can not be below 21ÉC (70ÉF). (1) Raise hood of vehicle.
(2) With gear selector in park or neutral, and park
brake set, start engine and allow to idle at 1300 rpm. (3) Set the A/C controls to A/C and High blower.
(6) If the high pressure gauge reads below 2963
kPa (430 psi) 6138 kPa (20 psi) the compressor
clutch should be engaged.
CAUTION: Do not allow engine to overheat when ra-
diator air flow is blocked.
(7) Block radiator air flow with a suitable cover to
increase the high side pressure to at least 3100 kPa
(450 psi). Compressor clutch should disengage. (8) Remove cover from front of vehicle to allow
high side pressure to decrease. When pressure drops
below 1826 kPa (265 psi), compressor clutch should
engage.
REMOVAL AND INSTALLATION
(1) Using a refrigerant recovery machine, remove
the refrigerant from the A/C system.
Fig. 3 Remove Shaft Seal
Fig. 4 Shaft Seal Protector
Fig. 5 Install Shaft Seal
Fig. 6 Variable Displacement CompressorÐModel 6C17
Ä HEATING AND AIR CONDITIONING 24 - 21
Page 2328 of 2438

FIXED DISPLACEMENT COMPRESSORÐMODEL 10PA17 INDEX
page page
Compressor ............................. 24
Compressor Clutch/Coil Assembly ............ 24
Compressor Front Shaft Seal ............... 27 Compressor High-Pressure Relief Valve
....... 30
Refrigerant System Diagnosis ............... 30
COMPRESSOR
COMPRESSOR NOISE
Excessive noise that occurs when the air condition-
ing is being used, can be caused by:
² Loose bolts
² Mounting brackets
² Loose clutch
² Excessive high refrigerant system operating pres-
sure Verify compressor drive belt condition, proper re-
frigerant charge and head pressure before compressor
repair is performed. For noise diagnostic procedures, refer to the Com-
pressor Noise and Compressor Clutch Diagnosis
chart in this section.
REMOVAL AND INSTALLATION
The A/C compressor may be removed and posi-
tioned without discharging the refrigerant system.
Discharging is not necessary if removing the A/C
compressor clutch/coil assembly, engine, cylinder
head, or generator.
WARNING: REFRIGERANT PRESSURES REMAIN
HIGH EVEN THOUGH THE ENGINE MAY BE
TURNED OFF. BEFORE REMOVING A FULLY
CHARGED COMPRESSOR, REVIEW THE SAFETY
PRECAUTIONS AND WARNINGS SECTION IN THIS
GROUP. DO NOT TWIST OR KINK THE REFRIGER-
ANT LINES WHEN REMOVING A FULLY CHARGED
COMPRESSOR. SAFETY GLASSES MUST BE
WORN.
(1) Disconnect Negative battery cable.
(2) Loosen and remove drive belts (refer to Group
7, Cooling System) and disconnect compressor clutch
wire lead. (3) Remove refrigerant lines from compressor (if
necessary). (4) Remove compressor attaching nuts and bolts.
(5) Remove compressor. If refrigerant lines were
not removed, lift compressor/clutch assembly and tie
it to a suitable component. To install, reverse the preceding operation. If nec-
essary, refer to Charging Refrigerant System in the
Refrigerant Service Procedures section.
COMPRESSOR CLUTCH/COIL ASSEMBLY
CLUTCH INOPERATIVE
The air conditioning compressor clutch electrical
circuit is controlled by the engine controller. The
controller is located in the engine compartment out-
board of the battery. If the compressor clutch does not engage:
Verify refrigerant charge.
If the compressor clutch still does not engage check
for battery voltage at the low pressure or differential
pressure cut-off switch located on the expansion
valve. If voltage is not detected, refer to:
² Group 8W, Wiring Diagrams.
² The appropriate Powertrain Diagnostic Procedures
Manual for diagnostic information. If voltage is detected at the cut-off switch, recon-
nect switch. Then check for battery voltage between
the compressor clutch connector terminals. If voltage is detected, perform A/C Clutch Coil
Tests.
CLUTCH COIL TESTS
(1) Verify battery state of charge. (Test indicator
in battery should be green). (2) Connect an ammeter (0-10 ampere scale) in se-
ries with the clutch coil terminal. Use a volt meter
(0-20 volt scale) with clip leads measuring voltage
across the battery and A/C clutch. (3) With A/C control in A/C mode and blower at
low speed, start the engine and run at normal idle. (4) The A/C clutch should engage immediately and
the clutch voltage should be within two volts of the
battery voltage. If the A/C clutch does not engage,
test the fusible link. (5) The A/C clutch coil is acceptable if the current
draw is 2.0 to 3.7 amperes at 11.5-12.5 volts at clutch
coil. This is with the work area temperature at 21ÉC
(70ÉF). If voltage is more than 12.5 volts, add electri-
cal loads by turning on electrical accessories until
voltage reads below 12.5 volts. If coil current reads zero, the coil is open and
should be replaced. If the ammeter reading is 4 am-
peres or more, the coil is shorted and should be re-
placed. If the coil voltage is not within two volts of
the battery voltage, test clutch coil feed circuit for
excessive voltage drop.
24 - 24 HEATING AND AIR CONDITIONING Ä