change time CHRYSLER VOYAGER 1996 Owner's Guide

Page 1341 of 1938

ances the two solenoids to maintain the set speed.
Refer to Group 8H for speed control information.
TACHOMETERÐPCM OUTPUT
The PCM supplies engine RPM to the instrument
panel tachometer through the CCD Bus. The CCD
Bus is a communications port. Various modules use
the CCD Bus to exchange information. Refer to
Group 8E for more information.
THROTTLE BODY
On all engine assemblies (2.4, 3.0, and 3.3/3.8L)
the throttle body's are located on the left side of the
intake manifold plenum. The throttle body houses
the throttle position sensor and the idle air control
motor. Air flow through the throttle body is con-
trolled by a cable operated throttle blade located in
the base of the throttle body (Fig. 43) or (Fig. 44) or
(Fig. 45).
DIAGNOSIS AND TESTING
VISUAL INSPECTIONÐ2.4L ENGINE
A visual inspection for loose, disconnected, or mis-
routed wires and hoses should be made before
attempting to diagnose or service the fuel injection
system. A visual check helps save unnecessary test
and diagnostic time. A thorough visual inspection will
include the following checks:
(1) Check ignition cable routing from the coil pack
to the spark plugs. Verify the cable are routed in the
correct order and are fully seated to the coil and
spark plug.
(2) Check direct ignition system (DIS) coil electri-
cal connection for damage and a complete connection
to the coil pack (Fig. 46).
Fig. 43 Throttle BodyÐ2.4L
Fig. 44 Throttle BodyÐ3.0L
NSFUEL SYSTEM 14 - 47
DESCRIPTION AND OPERATION (Continued)

Page 1380 of 1938

FUEL HEATER RELAY TEST
The fuel heater relay is located in the Power Dis-
tribution Center (PDC). Refer to RelaysÐOperation/
Testing in Fuel Ingection System section of this
group for test procedures.
FUEL INJECTOR TEST
The fuel injection nozzels, located on the engine
cylinder head, spray fuel under high pressure into
the individual combustion chambers. Pressurized
fuel, delivered by the fuel injection pump, unseats a
spring-loaded needle valve inside the injector, and
the fuel is atomized as it escapes through the injector
opening into the engine's combustion chamber. If the
fuel injector does not operate properly, the engine
may misfire, or cause other driveability problems.
A leak in the injection pump±to±injector high±pres-
sure fuel line can cause many of the same symptoms
as a malfunctioning injector. Inspect for a leak in the
high±pressure lines before checking for a malfunc-
tioning fuel injector.
WARNING: THE INJECTION PUMP SUPPLIES HIGH-
±PRESSURE FUEL OF UP TO APPROXIMATELY
45,000 KPA (6526 PSI) TO EACH INDIVIDUAL INJEC-
TOR THROUGH THE HIGH±PRESSURE LINES. FUEL
UNDER THIS AMOUNT OF PRESSURE CAN PENE-
TRATE THE SKIN AND CAUSE PERSONAL INJURY.
WEAR SAFETY GOGGLES AND ADEQUATE PRO-
TECTIVE CLOTHING. AVOID CONTACT WITH FUEL
SPRAY WHEN BLEEDING HIGH±PRESSURE FUEL
LINES.
WARNING: DO NOT BLEED AIR FROM THE FUEL
SYSTEM OF A HOT ENGINE. DO NOT ALLOW FUEL
TO SPRAY ONTO THE EXHAUST MANIFOLD WHEN
BLEEDING AIR FROM THE FUEL SYSTEM.
To determine which fuel injector is malfunctioning,
run the engine and loosen the high±pressure fuel line
nut at the injector (Fig. 21). Listen for a change in
engine speed. If engine speed drops, the injector was
operating normally. If engine speed remains the
same, the injector may be malfunctioning. After test-
ing, tighten the line nut to 30 N´m (22 ft. lbs.)
torque. Test all injectors in the same manner one at
a time.
Once an injector has been found to be malfunction-
ing, remove it from the engine and test it. Refer to
the Removal/Installation section of this group for pro-
cedures.
After the injector has been removed, install it to a
bench±mount injector tester. Refer to operating
instructions supplied with tester for procedures.
The opening pressure or ªpopº pressure should be
15,000±15,800 kPa (2175±2291 psi). If the fuel injec-tor needle valve is opening (ªpoppingº) to early or to
late, replace the injector.
FUEL INJECTOR SENSOR TEST
The fuel injector sensor is used only on the fuel
injector for the number±1 cylinder (Fig. 22). It is not
used on the injectors for cylinders number 2, 3, or 4.
To test the sensor, unplug the sensor connector
(Fig. 22) from the engine wiring harness. Check
resistance across terminals. Resistance should be 110
ohms610 ohms at 20ÉC (68ÉF). Replace sensor if
specification cannot be met.
FUEL INJECTION PUMP TEST
The injection pump is not to be serviced or
the warranty may be voided. If the injection
pump requires service, the complete assembly
must be replaced.
Incorrect injection pump timing (mechanical or
electrical) can cause poor performance, excessive
smoke and emissions and poor fuel economy.
Fig. 21 Typical Inspection of Fuel Injector
Fig. 22 Fuel Injector Sensor Location
14 - 12 FUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINENS/GS
DIAGNOSIS AND TESTING (Continued)

Page 1476 of 1938

GENERAL INFORMATION
31TH TRANSAXLE
NOTE: Safety goggles should be worn at all times
when working on these transaxles.
This transaxle combines torque converter, three
speed transmission, final drive gearing, and differen-
tial into a front wheel drive system. The identifica-
tion markings and usage of the transaxle are charted
in Diagnosis and Tests.
NOTE: Transaxle operation requirements are differ-
ent for each vehicle and engine combination. 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 three primary
areas:
(1) Main center line plus valve body.
(2) Transfer shaft center line (includes governor
and parking sprag).
(3) Differential center line.
(4) Center distances between the main rotating
parts in these three areas are held precise to main-
tain a low noise level.
(5) The torque converter, transaxle area, and dif-
ferential are housed in an integral aluminum die
casting.The differential oil sump is common
with the transaxle sump. Separate filling of the
differential is NOT necessary.
(6) The torque converter is attached to the crank-
shaft through a flexible driving plate. Cooling of the
converter is accomplished by circulating the tran-
saxle fluid through a remote cooler. There are two
types of coolers used. An oil-to-water type cooler
located in the radiator side tank and/or an oil-to air
heat exchanger. The torque converter assembly is a
sealed unit that cannot be disassembled.
(7) The transaxle fluid is filtered by an internal fil-
ter attached to the lower side of the valve body
assembly.
(8) 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.
(9) The transaxle consists of:
²Two multiple-disc clutches
²An overrunning clutch
²Two servos
²A hydraulic accumulator
²Two bands²Two planetary gear sets
This provides three forward ratios and a reverse
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
front clutch retainer. The hydraulic system consists
of an oil pump, and a single valve body which con-
tains 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 helical gears to
the transfer shaft. This gear set is a factor of the
final drive (axle) ratio. The shaft also carries the gov-
ernor and parking sprag. An integral helical gear on
the transfer shaft drives the differential ring gear.
The final drive gearing is completed with one of two
gear ratios of 2.98 or 3.19 depending on model and
application.
FLUID LEVEL AND CONDITION
NOTE: The transmission and differential sump have
a common oil sump with a communicating opening
between the two.
The torque converter fills in both the P Park and N
Neutral positions. Place the selector lever in P Park
to be sure that the fluid level check is accurate.The
engine should be running at idle speed for at
least one minute, with the vehicle on level
ground. This will assure complete oil level sta-
bilization between differential and transmis-
sion.The fluid should be at normal operating
temperature (approximately 82 C. or 180 F.). The
fluid level is correct if it is in the HOT region (cross-
hatched area) on the dipstick.
Low fluid level can cause a variety of conditions
because it allows the pump to take in air along with
the fluid. As in any hydraulic system, air bubbles
make the fluid spongy, therefore, pressures will be
low and build up slowly.
Improper filling can also raise the fluid level too
high. When the transaxle has too much fluid, the
gears churn up foam and cause the same conditions
which occur with a low fluid level.
In either case, the air bubbles can cause overheat-
ing, fluid oxidation, and varnishing. This can inter-
fere with normal valve, clutch, and servo operation.
Foaming can also result in fluid escaping from the
transaxle dipstick where it may be mistaken for a
leak.
Along with fluid level, it is important to check the
condition of the fluid. When the fluid smells burned,
and is contaminated with metal or friction material
particles, a complete transaxle overhaul is needed.
Be sure to examine the fluid on the dipstick closely.
21 - 2 TRANSAXLE AND POWER TRANSFER UNITNS

Page 1545 of 1938

41TE AUTOMATIC TRANSAXLE
INDEX
page page
GENERAL INFORMATION
41TE FOUR SPEED AUTOMATIC TRANSAXLE . 71
FLUID LEVEL AND CONDITION............. 72
SELECTION OF LUBRICANT............... 72
SPECIAL ADDITIVES..................... 72
DESCRIPTION AND OPERATION
ADAPTIVE CONTROLS................... 73
CLUTCH AND GEAR..................... 72
ELECTRONICS......................... 73
GEARSHIFT AND PARKING LOCK CONTROLS . 74
HYDRAULICS........................... 73
ON-BOARD DIAGNOSTICS................ 74
SENSORS............................. 73
SHIFT POSITION INDICATOR.............. 74
SOLENOIDS............................ 73
TORQUE MANAGEMENT.................. 74
TRANSMISSION CONTROL MODULE........ 74
TRANSMISSION RANGE SENSOR........... 74
DIAGNOSIS AND TESTING
41TE TRANSAXLE GENERAL DIAGNOSIS..... 75
CLUTCH AIR PRESSURE TESTS............ 77
FLUID LEAKAGE-TORQUE CONVERTER
HOUSING AREA....................... 78
HYDRAULIC PRESSURE TESTS............ 75
ROAD TEST............................ 75
SHIFT POSITION INDICATOR.............. 78
SERVICE PROCEDURES
ALUMINUM THREAD REPAIR.............. 81
FLUID AND FILTER CHANGE............... 79
FLUID DRAIN AND REFILL................. 81
FLUSHING COOLERS AND TUBES.......... 81OIL PUMP VOLUME CHECK............... 82
PINION FACTOR PROCEDURE............. 83
TRANSAXLE QUICK LEARN PROCEDURE.... 82
REMOVAL AND INSTALLATION
GEARSHIFT CABLE...................... 83
MANUAL VALVE LEVER (SHIFT LEVER)...... 84
OIL PUMP SEAL......................... 92
SOLENOID ASSEMBLY-REPLACE........... 85
SPEED SENSOR-INPUT................... 86
SPEED SENSOR-OUTPUT................. 86
TRANSAXLE........................... 89
TRANSMISSION CONTROL MODULE........ 87
TRANSMISSION RANGE SENSOR........... 85
VALVE BODY........................... 88
DISASSEMBLY AND ASSEMBLY
DIFFERENTIAL REPAIR.................. 139
INPUT CLUTCHES-RECONDITION.......... 110
TRANSAXLE ASSEMBLE................. 122
TRANSAXLE DISASSEMBLE............... 95
VALVE BODY RECONDITION............... 92
CLEANING AND INSPECTION
CLEANING VALVE BODY................. 144
ADJUSTMENTS
GEARSHIFT CABLE ADJUSTMENT......... 144
SCHEMATICS AND DIAGRAMS
41TE TRANSAXLE HYDRAULIC SCHEMATICS . 145
SPECIFICATIONS
41TE AUTOMATIC TRANSAXLE............ 158
41TE TORQUE SPECIFICATIONS.......... 158
SPECIAL TOOLS
41TE AUTOMATIC TRANSAXLE............ 159
GENERAL INFORMATION
41TE FOUR SPEED AUTOMATIC TRANSAXLE
The 41TE four-speed FWD transaxle uses fully-
adaptive controls. Adaptive controls are those which
perform their functions based on real-time feedback
sensor information. The transaxle uses hydraulically
applied clutches to shift a planetary gear train.
TRANSAXLE IDENTIFICATION
The 41TE transaxle identification code is printed
on a label. The label is located on the transaxle case
next to the solenoid assembly (Fig. 1).
Fig. 1 Identification Tag Location
NSTRANSAXLE AND POWER TRANSFER UNIT 21 - 71

Page 1547 of 1938

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:
²Manual shift lever select function
²Main line pressure regulation
²Torque 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 con-
verter clutch control valve. This valve locks out the
1st gear reaction element with the application of 2nd,
direct, 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 sequence of commands must be used to
move the solenoid TCC control valve. This precludes
any application of the 1st gear reaction element with
other elements applied. It also allows one solenoid to
control two friction elements.
Small, high-rate accumulators are provided in each
controlled friction element circuit. These serve to
absorb the pressure responses, and allow the controls
to read and respond to changes that are occurring.
SOLENOIDS
The solenoid valves perform most control functions,
these valves must be extremely durable and tolerant
of dirt. For that reason hardened-steel poppet and
ball valves are used. These are free from any close
operating clearances. The solenoids operate the
valves directly without any intermediate element.
Direct operation means that these units must have
very high output. They must close against the size-
able flow areas and high line pressures. Fast
response is also required to meet the control require-
ments.
Two of the solenoids are normally-venting and two
are normally-applying; this was done to provide a
default mode of operation. With no electrical power,
the transmission provides 2nd gear in (OD), (3), or
(L) shift lever positions. All other transmission lever
positions will operate normally. The choice of 2nd
gear was made to provide adequate breakaway per-
formance while still accommodating highway speeds.
SENSORS
There are three pressure switches to identify sole-
noid application. There are two speed sensors to read
input (torque converter turbine) and output (parking
sprag) speeds. There is also a transmission range
sensor to indicate the manual shift lever position.
The pressure switches are incorporated in an assem-
bly with the solenoids. Engine speed, throttle posi-tion, temperature, etc., are also observed. Some of
these signals are read directly from the engine con-
trol sensors; others are read from a multiplex circuit
with the powertrain control module.
ELECTRONICS
The 41TE Transmission Control Module (TCM) is
located underhood in a potted, die-cast aluminum
housing. The module used is a new controller called
EATX III. The TCM has a sealed, 60-way connector.
ADAPTIVE CONTROLS
These controls function by reading the input and
output speeds over 140 times a second and respond-
ing to each new reading. This provides the precise
and sophisticated friction element control needed to
make smooth clutch-to-clutch shifts for all gear
changes. The use of overrunning clutches or other
shift quality aids are not required. As with most
automatic transaxles, all shifts involve releasing one
element and applying a different element. In simpli-
fied terms, the upshift logic allows the releasing ele-
ment to slip backwards slightly. This ensures that it
does not have excess capacity. The apply element is
filled until it begins to make the speed change to the
higher gear. The apply pressure is then controlled to
maintain the desired rate of speed change. This con-
tinues until the shift is made. The key to providing
excellent shift quality is precision. For example, the
release element for upshifts is allowed to slip back-
wards slightly. The amount of that slip is typically
less than a total of 20 degrees. To achieve that pre-
cision, the TCM learns the traits of the transaxle
that it is controlling. It learns the release rate of the
releasing element and the apply time of the applying
element. It also learns the rate at which the apply
element builds pressure sufficient to begin making
the speed change. This method achieves more preci-
sion than would be possible with exacting tolerances.
It can also adapt to any changes that occur with age
or environment.
For kickdown shifts, the control logic allows the
releasing element to slip. Then controls the rate at
which the input (and engine) accelerate. When the
lower gear speed is achieved, the releasing element
reapplies to maintain that speed until the apply ele-
ment is filled. This provides quick response since the
engine begins to accelerate immediately. This also
provides a smooth torque exchange since the release
element can control the rate of torque increase. This
control can make any powertrain feel more respon-
sive without increasing harshness.
Adaptive controls respond to input speed changes.
They compensate for changes in engine or friction
element torque and provide good, consistent shift
quality for the life of the transaxle.
NSTRANSAXLE AND POWER TRANSFER UNIT 21 - 73
DESCRIPTION AND OPERATION (Continued)

Page 1824 of 1938

COOLDOWN TEST ENTRY
TO INITIATE TESTS:
²Set Blower motor ON HIGH
²Set Mode position to Panel
²Open all A/C outlets
²Set Temperature to Cold (Both slide pots if
equipped)
²Depress WASH and A/C simultaneously for 5
Seconds
NOTE: Prior to start of test, If the evaporator is
already cold, the system will fail test. To correct,
operate system with A/C OFF and the blower motor
ON high for three minutes prior to starting test.
RESULTS:
²All LED's will turn on for 5 Seconds
²Cooldown Test is running when A/C and
RECIRC. are alternately flashing. If A/C and
RECIRC. are flashing simultaneously, Cooldown has
failed.
CALIBRATION DIAGNOSTICS AND
COOLDOWN ABORT
Test can be aborted by doing one of the following:
²Depressing Rear Window Defogger, RECIRC and
Rear Wiper buttons.
²Cycling Ignition OFF and then ON.
²Control will automatically abort after 15 min-
utes from the time Calibration Diagnostics and
Cooldown was entered.
The HVAC control module will return to normal
operation or may indicate unsuccessful Calibration
Diagnostics or Cooldown test by LED's flashing
simultaneously.
EEPROM DATA
Calibration Diagnostics, Cooldown Status and
evaporator temperature Fin Sensor values are stored
in an EEPROM memory internal to the control. The
microcomputer within the HVAC control module uses
this information:
²To determine if Cooldown needs to run
²For proper position of the Heater-A/C unit
assembly doors
ACTUATOR CALIBRATION AND
DIAGNOSTICS.
NOTE: Do not run actuators unless they are prop-
erly mounted on the HVAC control module.
Actuator end point calibration takes approximately
60 seconds. The REAR WIPER and INTERMITTENT
LED's will flash alternately during the test. The con-
trol will cycle the Blend actuator(s) to the Heat stopfirst then back to Cold. After the Blend actuator(s)
have been calibrated the Mode actuator will be cycled
to Defrost and then to Panel. Successful calibration
is defined as actuator travel falling within their min-
imum and maximum limits.
BLEND/PASSENGER ACTUATOR BACKGROUND
The Blend/Passenger Actuator can move the tem-
perature door in two directions. When the voltage at
Pin 12 of the control module is high, about 11.5 volts,
and the voltage at Pin 17 is low, about 1.5 volts, the
door will move towards the Heat position. When Pin
17 is High and Pin 12 is Low the door will move
towards the Cold position. When both Pins are high
or both Pins are low, the actuator will not move. The
Blend/Passenger feedback signal is a voltage signal
that is supplied by the actuator to the control. The
signal will be about 4.0 volts in the Heat position
and 1.0 volt in the Cold position. As the position of
the Blend/Passenger actuator changes, so will the
feedback signal. The feedback signal is necessary for
the correct positioning of the temperature door.
DRIVER ACTUATOR BACKGROUND
The Driver Actuator can move the temperature
door in two directions. When the voltage at Pin 15 of
the control module is high, about 11.5 volts, and the
voltage at Pin 13 is low, about 1.5 volts the door will
move towards the Cold position. When Pin 13 is High
and Pin 15 is Low the door will move towards the
Heat position. When both Pins are high or when both
Pins are low, the actuator will not move. The Driver
feedback signal is a voltage signal that is supplied by
the actuator to the control. The signal will be about
4.0 volts in the Heat position and 1.0 volt in the Cold
position. As the position of the Driver Actuator
changes, so will the feedback signal. The feedback
signal is necessary for the correct positioning of the
temperature door.
MODE ACTUATOR BACKGROUND
The Mode actuator can move the mode door in two
directions. When the voltage at Pin 18 of the control
module is high, about 11.5 volts, and the voltage at
Pin 12 is low, about 1.5 volts the door will move
towards the Panel position. When Pin 12 is High and
Pin 18 is Low the door will move towards the Defrost
position. When both Pin are high or when both Pins
are low, the actuator will not move. The Mode door
feedback signal is a voltage signal that is supplied by
the actuator to the control. The signal will be about
4.5 volts in the Panel position and 0.5 volts in the
Defrost position. As the position of the Mode actuator
changes, so will the feedback signal. The feedback
signal is necessary for the correct positioning of the
mode door.
24 - 8 HEATING AND AIR CONDITIONINGNS
DIAGNOSIS AND TESTING (Continued)

Page 1825 of 1938

FAIL CODES/LEVEL DISPLAY
Fail Codes/Level are displayed using the REAR
WIPER and INTERMITTENT LED's flashing in the
sequence indicated below. The REAR WIPER LED
represents the Level and the INTERMITTENT LED
represents the Value. After Calibration/Diagnostics is
completed, the control will begin flashing Level 1
codes. Depressing the WASH button will cycle to
Level 2, depressing WASH again will cycle to Level 3.
Each time the WASH button is depressed will cycle
to the next level. After Level 5 is reached, you will
cycle back to Level 1. If the Control is a Heater Only
you will only cycle from Levels 1 to 3.
TEMPERATURE AND MODE POTENTIOMETER
DIAGNOSTICS
The Temperature and Mode Potentiometer can be
tested after calibration is complete by pressing the
WASH button and cycling to Levels 2, 3 or 5 as dis-
played by the REAR WIPER LED. On Heater Only
units you can only cycle to Levels 2 and 3. In eachindividual test the INTERMITTENT LED flash rate
will change as the Temperature or Mode potentiome-
ter is moved from one end to the other, see Potenti-
ometer vs. Position and Flash Rate table.
EVAPORATOR PROBE TEMPERATURE
DIAGNOSTICS
The evaporator probe can be tested by using the
INTERMITTENT LED to display the actual temper-
ature the sensor is reading. The HVAC control mod-
ule can only display temperatures from 1 to 99
degrees. To read the temperature, perform the follow-
ing:
²Set Blower motor to any speed other than OFF
²Set A/C to ON, if A/C Clutch does not engage
make sure Fail Codes 5 and 6 are cleared.To clear
the error code 5 and 6 the evaporator probe and/or
the wiring repair needs to be completed. Then, press
and hold the intermittent wipe button for 5 seconds.
²Run Diagnostics (Depress REAR WIPER and
REAR WASH)
²When Diagnostics is complete, Cycle to Level 4.
Display Sequence is as follows:
²REAR WIPER LED will display the Level
²INTERMITTENT LED will display ten's digit
²Short Pause
²INTERMITTENT LED will display the one's
digit.
The HVAC control module will continue to cycle
the Level and then Temperature until the level is
changed or Calibration Diagnostics and Cooldown
test is exited.
HVAC CONTROL DIAGNOSTIC CONDITIONS
For wiring circuits, wiring connectors, and Pin
numbers, refer to Group 8W, Wiring Diagrams.
After calibration, Rear Wiper LED flashing
once, Intermittent LED not flashing.
The system has passed calibration. Press the Rear
Wiper button to exit calibration.
WIPE BUTTON LED
LEVEL DISPLAY
1 FAIL CODES
2 MODE POTENTIOMETER TEST
3 BLEND/PASS. POTENTIOMETER TEST
4 EVAPORATOR PROBE (A/C AND ZONE
UNITS ONLY)
5 DRIVER POTENTIOMETER (ZONE UNITS
ONLY)
LEVEL 1±FAILURE CODE VALUES
(INTERMITTENT WIPE BUTTON LED)
CODE DEFINITION
0 PASSED ALL TESTS
1 MODE ACTUATOR DID NOT REACH
DEFROST POSITION
2 MODE ACTUATOR DID NOT REACH
PANEL POSITION
3 BLEND/PASS. ACTUATOR DID NOT
REACH COLD STOP
4 BLEND PASS. ACTUATOR DID NOT
REACH HEAT STOP
5 EVAPORATOR PROBE OPEN
6 EVAPORATOR PROBE SHORTED
7 DRIVER ACTUATOR DID NOT REACH
COLD STOP
8 ZONE/DRIVER ACTUATOR DID NOT
REACH HEAT STOP
9 CONTROL HEAD INTERNAL FAILURE
POTENTIOMETER VS. POSITION AND FLASH
RATE
POTENTIOM-
ETERINTERMIT-
TENT LED
FASTER
FLASH RATEINTERMITTENT
LED SLOWER
FLASH RATE
MODE PANEL DEFROST
BLEND/PASS. HOT COLD
DRIVER HOT COLD
NSHEATING AND AIR CONDITIONING 24 - 9
DIAGNOSIS AND TESTING (Continued)

Page 1826 of 1938

After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing once. The
mode actuator did not reach defrost position.
(1) Using a voltmeter, check the mode door actua-
tor wiring connector. Check Pin 1 for battery voltage.
Move the HVAC control from the defrost to panel
position, and check Pin 6 voltage it should change
from 0.5 - 1 volts to 3.5 - 4.5 volts. If voltage is OK,
go to Step 2. If not OK, check for loose or corroded
connector, open or shorted circuit and repair as nec-
essary.
(2) Remove actuator, and check if the gear pins are
in the correct track on cam or if they are binding. If
OK, go to Step 3. If not OK, repair as necessary.
(3) Check for binding door, if door is binding repair
as necessary. If gears and door are OK, replace
actuator.
(4) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing twice. The
mode actuator did not reach panel position.
(1) Using a voltmeter, check the mode door actua-
tor wiring connector. Check Pin 1 for battery voltage.
Move the HVAC control from panel to defrost posi-
tion, and check Pin 6 voltage it should change from
3.5 - 4.5 volts to 0.5 - 1 volts. If voltage is OK, go to
Step 2. If not OK, check for loose or corroded connec-
tor, open or shorted circuit and repair as necessary.
(2) Remove actuator, and check if the gear pins are
in the correct cam track or binding. If OK, go to Step
3. If not OK, repair as necessary.
(3) Check for binding door, if door is binding repair
as necessary. If gears and door are OK, replace
actuator.
(4) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing three times.
The main temperature actuator/passenger
temperature actuator on a zone system did
not reach cold stop.
(1) Check if the correct HVAC control module was
used.
(2) Using a voltmeter, check the temperature door
actuator wiring connector. Check Pin 1 for battery
voltage. Move the HVAC control from the cold to hot
position, and check Pin 5 voltage it should change
from 0.5 - 4 volts to 3.5 - 4.5 volts. If voltage is OK,
go to Step 3. If not OK, check for loose or corroded
connector, open or shorted circuit and repair as nec-
essary.(3) Remove actuator, and check if gear pins are in
the correct cam track or binding. If OK, go to Step 4.
If not OK, repair as necessary.
(4) Check for binding door, if door is binding repair
as necessary. If gears and door are OK, replace
actuator.
(5) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing four times.
The main temperature actuator/passenger
temperature actuator on a zone system did
not reach hot stop.
(1) Check if the correct HVAC control module was
used.
(2) Using a voltmeter, check the temperature door
actuator wiring connector. Check Pin 1 for battery
voltage. Move the HVAC control from hot to cold
position and check Pin 5 voltage it should change
from 3.5 -4.5 volts 0.5 - 1.5 volts. If voltage is OK, go
to Step 3. If not OK, check for loose or corroded con-
nector, open or shorted circuit and repair as neces-
sary.
(3) Remove actuator, and check if the gear pins are
in the correct track on cam or if they are binding. If
OK, go to Step 4. If not OK, repair as necessary.
(4) Check for binding door, if door is binding repair
as necessary. If gears and door are OK, replace
actuator.
(5) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing five times.
The evaporator probe is open.
(1) Using a voltmeter, check Pin 1 of the evapora-
tor probe wiring connector for 0.1 - 4.75 volts. If OK,
go to Step 2. If not OK, if greater than 4.75 volts
check for loose or corroded connector, open circuit
and repair as necessary.
(2) Using a ohmmeter, check Pin 2 for a good
ground, If OK, go to Step 3. If not OK, check for loose
or corroded connector, open or shorted circuit and
repair as necessary.
(3) If ground and power circuit are OK, replace
Evaporator Probe.
(4) Once repairs are completed, press the intermit-
tent button about 5 seconds until all LED's light to
remove fault code from memory. Then repeat the Cal-
ibration Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
24 - 10 HEATING AND AIR CONDITIONINGNS
DIAGNOSIS AND TESTING (Continued)

Page 1827 of 1938

After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing six times. The
evaporator probe is shorted.
(1) Using a voltmeter, check Pin 1 of the evapora-
tor probe wiring connector for 0.1 - 4.75 volts. If OK,
go to Step 2. If less than 0.1 volts, check for loose or
corroded connector, open or shorted circuit and repair
as necessary.
(2) Using a ohmmeter, check Pin 2 for a good
ground, If OK, go to Step 3. If not OK, check for
shorted circuit and repair as necessary.
(3) If ground and power circuit are OK, replace
Evaporator Probe
(4) Once repairs are completed, press the intermit-
tent button about 5 seconds until all LED's light to
remove fault code from memory. Then repeat the Cal-
ibration Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing seven times.
The Driver's temperature actuator on a zone
system did not reach cold stop.
(1) Check if the correct HVAC control module was
used.
(2) Using a voltmeter, check at the temperature
door actuator wiring connector, check Pin 1 for bat-
tery voltage. Move the HVAC control from cold to the
hot position, check Pin 4 voltage it should change
from 0.5 - 1.5 volts 3.5 - 4.5 volts. If voltage is OK, go
to Step 3. If not OK, check for loose or corroded con-
nector, open or shorted circuit and repair as neces-
sary.
(3) Remove actuator, and check if the gear pins are
in the correct track on cam or if they are binding. If
OK, go to Step 4. If not OK, repair as necessary.
(4) Check for binding doors, if door are binding
repair as necessary. If gears and door are OK, replace
actuator.
(5) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing eight times.
The Driver's temperature actuator on a zone
system did not reach hot stop.
(1) Check if the correct HVAC control module was
used.
(2) Using a voltmeter, check at the temperature
door actuator wiring connector, check Pin 1 for bat-
tery voltage. Move the HVAC control from hot to cold
position, Pin 4 voltage it should change from 3.5 - 4.5
volts to 0.5 - 1.5 volts. If voltage is OK, go to Step 3.
If not OK, check for loose or corroded connector, open
or shorted circuit and repair as necessary.(3) Remove actuator, and check if the gear pins are
in the correct track on cam or if they are binding. If
OK, go to Step 4. If not OK, repair as necessary.
(4) Check for binding door, if door is binding repair
as necessary. If gears and door are OK, replace
actuator.
(5) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration, Rear Wiper LED flashing
once, Intermittent LED flashing nine times.
The HVAC control module, has a internal
failure.
(1) Replace the HVAC control module.
(2) Once repairs are completed repeat the Calibra-
tion Diagnostic and Cooldown test. Repeating the
test is necessary to clear the fault codes.
After calibration and testing the A/C and
RECIRC LED flashing simultaneously. Failed
Cooldown test.
(1) Determine if the refrigerant system is operat-
ing correctly:
²Check the outlet air temperature
²Feel the compressor suction plumbing, is it hot?
(2) If not OK, go to Step 3. If OK, repeat the Cal-
ibration Diagnostic and Cooldown test.
(3) If system does not seem to be operating cor-
rectly, perform diagnostics for poor performance:
²Low refrigerant charge
²No charge
²Compressor not operating
Verify that the test was done with the evaporator
at room temperature. The test consists of starting
the compressor and measuring the time it takes for
the evaporator temperature to fall 7ÉC (20ÉF). If the
compressor has been running, the evaporator is cold
already and will not be capable of falling 7ÉC (20ÉF).
If the test was run with a cold evaporator, turn A/C
off and turn the blower motor switch to high position
for 3 to 5 minutes till the evaporator is to room tem-
perature. Then repeat the Calibration Diagnostic and
Cooldown test.
If refrigerant system is performing properly and
the system will not pass test. Repeat the Calibration
Diagnostic and Cooldown test to determine if the
evaporator temperature FIN sensor has developed an
open or a short circuit. If the HVAC control module
still passes Calibration test, verify Cooldown test
manually with a pocket thermometer. The outlet air
temperature must drop at least 7ÉC (20ÉF) within
two minutes. If the vehicle passes with the manual
thermometer, take HVAC control to level 4 (evapora-
tor probe temperature readout) and repeat the
Cooldown test. Ensure the evaporator is at room tem-
perature before starting test. Check if evaporator
NSHEATING AND AIR CONDITIONING 24 - 11
DIAGNOSIS AND TESTING (Continued)

Page 1873 of 1938

COOLDOWN TEST ENTRY
TO INITIATE TESTS:
²Set Blower motor ON HIGH
²Set Mode position to Panel
²Open all A/C outlets
²Set Temperature to Cold (Both slide pots if
equipped)
²Depress WASH and A/C simultaneously for 5
Seconds
NOTE: Prior to start of test, If the evaporator is
already cold, the system will fail test. To correct,
operate system with A/C OFF and the blower motor
ON high for three minutes prior to starting test.
RESULTS:
²All LED's will turn on for 5 Seconds
²Cooldown Test is running when A/C and
RECIRC. are alternately flashing. If A/C and
RECIRC. are flashing simultaneously, Cooldown has
failed.
CALIBRATION DIAGNOSTICS AND
COOLDOWN ABORT
Test can be aborted by doing one of the following:
²Depressing Rear Window Defogger, RECIRC and
Rear Wiper buttons.²Cycling Ignition OFF and then ON.
²Control will automatically abort after 15 min-
utes from the time Calibration Diagnostics and
Cooldown was entered.
The HVAC control module will return to normal
operation or may indicate unsuccessful Calibration
Diagnostics or Cooldown test by LED's flashing
simultaneously.
EEPROM DATA
Calibration Diagnostics, Cooldown Status and
evaporator temperature Fin Sensor values are stored
in an EEPROM memory internal to the control. The
microcomputer within the HVAC control module uses
this information:
²To determine if Cooldown needs to run
²For proper position of the Heater-A/C unit
assembly doors
ACTUATOR CALIBRATION AND
DIAGNOSTICS.
NOTE: Do not run actuators unless they are prop-
erly mounted on the HVAC control module.
Actuator end point calibration takes approximately
60 seconds. The REAR WIPER and INTERMITTENT
LED's will flash alternately during the test. The con-
trol will cycle the Blend actuator(s) to the Heat stop
first then back to Cold. After the Blend actuator(s)
have been calibrated the Mode actuator will be cycled
to Defrost and then to Panel. Successful calibration
is defined as actuator travel falling within their min-
imum and maximum limits.
BLEND/PASSENGER ACTUATOR BACKGROUND
The Blend/Passenger Actuator can move the tem-
perature door in two directions. When the voltage at
Pin 12 of the control module is high, about 11.5 volts,
and the voltage at Pin 17 is low, about 1.5 volts, the
door will move towards the Heat position. When Pin
17 is High and Pin 12 is Low the door will move
towards the Cold position. When both Pins are high
or both Pins are low, the actuator will not move. The
Blend/Passenger feedback signal is a voltage signal
that is supplied by the actuator to the control. The
signal will be about 4.0 volts in the Heat position
and 1.0 volt in the Cold position. As the position of
the Blend/Passenger actuator changes, so will the
feedback signal. The feedback signal is necessary for
the correct positioning of the temperature door.
DRIVER ACTUATOR BACKGROUND
The Driver Actuator can move the temperature
door in two directions. When the voltage at Pin 15 of
the control module is high, about 11.5 volts, and the
voltage at Pin 13 is low, about 1.5 volts the door will
LED'S PASS/FAILCORRECTIVE
ACTION
NO LED'S
FLASHING-
NORMAL
OPERATIONPASSED
CALIBRATION,
DIAGNOSTICS
AND
COOLDOWNNONE
REAR WIPER
AND
INTERMITTENT
LED'S FLASH
SIMULTANEOUSLYFAILED
CALIBRATION
DIAGNOSTICSRUN
CALIBRATION
TEST
A/C AND RECIRC
LED'S FLASH
SIMULTANEOUSLYFAILED
COOLDOWNRUN
COOLDOWN
TEST
REAR WIPER
AND
INTERMITTENT
LED'S ARE
FLASHING
SIMULTANEOUSLY
A/C AND RECIRC
LED'S ARE
FLASHING
SIMULTANEOUSLYFAILED
CALIBRATION,
DIAGNOSTICS
AND FAILED
COOLDOWN
TESTRUN
CALIBRATION
TEST
NS/GSHEATING AND AIR CONDITIONING 24 - 7
DIAGNOSIS AND TESTING (Continued)

Page:   < prev 1-10 11-20 21-30 31-40 41-50 next >