ESP CHEVROLET DYNASTY 1993 Workshop Manual

(5) This test checks pump output, pressure regula-
tion and condition of the low/reverse clutch hydraulic
circuit and shift schedule.
TEST TWO-SELECTOR IN DRIVE 2ND GEAR
(1) Attach gauge to the underdrive clutch tap.
(2) Move selector lever to the 3position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle
speed of 30 mph. (4) Underdrive clutch pressure should read 110 to
145 psi. (5) This test checks the underdrive clutch hydrau-
lic circuit as well as the shift schedule.
TEST THREE-OVERDRIVE CLUTCH CHECK
(1) Attach gauge to the overdrive clutch tap.
(2) Move selector lever to the circle Dposition.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle
speed of 20 mph. (4) Overdrive clutch pressure should read 74 to 95
psi. (5) Move selector lever to the 3position and in-
crease indicated vehicle speed to 30 mph. (6) The vehicle should be in second gear and over-
drive clutch pressure should be less than 5 psi. (7) This test checks the overdrive clutch hydraulic
circuit as well as the shift schedule.
TEST FOUR-SELECTOR IN CIRCLE DRIVE, OVERDRIVE GEAR
(1) Attach gauge to the 2/4 clutch tap.
(2) Move selector lever to the circle Dposition.
(3) Allow vehicle front wheels to turn and increase
throttle opening to achieve an indicated vehicle
speed of 30 mph. (4) The 2/4 clutch pressure should read 75 to 95
psi. (5) This test checks the 2/4 clutch hydraulic circuit.
TEST FIVE-SELECTOR IN CIRCLE DRIVE,
OVERDRIVE
(1) Attach gauge to the torque converter clutch off
pressure tap. (2) Move selector lever to the circle Dposition.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 50 mph.
CAUTION: Both wheels must turn at the same speed. (4) Torque converter clutch off pressure should be
less than 5 psi. (5) This test checks the torque converter clutch
hydraulic circuit.
TEST SIX-SELECTOR IN REVERSE
(1) Attach gauge to the reverse clutch tap.
(2) Move selector lever to the reverse position.
(3) Read reverse clutch pressure with output sta-
tionary (foot on brake) and throttle opened to achieve
1500 rpm. (4) Reverse clutch pressure should read 165 to 235
psi. (5) This test checks the reverse clutch hydraulic
circuit.
TEST RESULT INDICATIONS
(1) If proper line pressure is found in any one test,
the pump and pressure regulator are working properly. (2) Low pressure in all positions indicates a defec-
tive pump, a clogged filter, or a stuck pressure regula-
tor valve. (3) Clutch circuit leaks are indicated if pressures do
not fall within the specified pressure range. (4) If the overdrive clutch pressure is greater than 5
psi in step (6) of Test Three, a worn reaction shaft seal
ring is indicated.
CLUTCH AIR PRESSURE TESTS
Inoperative clutches can be located using a series of
tests by substituting air pressure for fluid pressure
(Figs. 2 and 3). The clutches may be tested by applying
air pressure to their respective passages after the valve
body has been removed and Tool 6056 has been in-
stalled. To make air pressure tests, proceed as follows: The compressed air supply must be free of all
dirt and moisture. Use a pressure of 30 psi. Remove oil pan and valve body. See Valve body
removal.
OVERDRIVE CLUTCH
Apply air pressure to the overdrive clutch apply
passage and watch for the push/pull piston to move
Fig. 1 Pressure Taps
Ä TRANSAXLE 21 - 95

41TE ON-BOARD DIAGNOSTICS INDEX
page page
CCD Bus .............................. 145
Diagnostic Trouble Code Charts ............ 146
Diagnostic Trouble Codes ................. 145
DRB II Scan Tool ....................... 146 General Information
...................... 145
Limp-In Mode .......................... 145
On-Board Diagnostics Information ........... 145
GENERAL INFORMATION
The information in this manual is designed to help
the technician understand and repair the transaxle
with the aid of the built in on-board diagnostics. Chrysler Corporation has developed a com-
plete set of diagnostic manuals which cover the
diagnosis of the 41TE transaxle. They have been
designed to make transaxle diagnosis accurate
and simple. Use these manuals with the DRB II
scan tool and the latest cartridge, when diagnos-
ing transaxle problems.
ON-BOARD DIAGNOSTICS INFORMATION
The 41TE transaxle is controlled and monitored by
the transmission control module. The transmission
control module monitors critical input and output
circuits within the transaxle. Some circuits are tested continuously; others are
checked only under certain conditions. Each circuit
monitored by the transmission control module has a
corresponding fault message assigned to it that can be
read with the DRB II scan tool. If the on-board diagnostic system senses that one of
the circuits is malfunctioning, the corresponding code
is stored in memory. If the malfunction goes away after
the code is stored, the transmission control module will
erase the code after 75 key cycles.
CCD BUS
In order to diagnose the 41TE transaxle, diagnostic
trouble codes in the transmission control module's
memory should be read. Use the Diagnostic Readout
Box (DRB II) scan tool to read codes. If more than one
diagnostic trouble code exists, diagnostic priority
should be given to the most recent code. With CCD bus
bias and communication problems, the DRB II scan
tool displays an appropriate message. Diagnostic
trouble codes might not be accessible until the bus
problem is fixed. The following is a list of probable
causes for a bus problem:
² Open or short to ground/battery in either or both
CCD bus wires (pins 4 and 43).
² Open or short to ground/battery in either or both
41TE transaxle's bias wires (pin 5 and 44) on vehicles
requiring the transaxle to bias the bus.
² Open or short to ground/battery in the diagnostic
connector bus wire. ²
Internal failure of any module connected to the bus.
The CCD bus should have 2.5 volts (+2.5 volts on
CCD+ and -2.5 volts on CCD-). The bus error message displayed by the DRB II scan
tool should be helpful in diagnosing the CCD bus. For more information on diagnosing CCD bus prob-
lems, refer to the 1993 Diagnostic Procedures Manual
(non-communication with the CCD bus). All other
problems refer to the 1993 Body Vehicle Communica-
tions Diagnostic Procedures Manual.
DIAGNOSTIC TROUBLE CODES
Diagnostic Trouble Codes are two-digit numbers that
identify which circuit is malfunctioning. A code can be
set for hydraulic and mechanical reasons as well as for
electrical problems. In most cases, codes do not pin-
point which specific component is defective. Diagnostic trouble codes can only be read with
the use of the DRB II scan tool or equivalent.
HARD FAULTS
Any Diagnostic trouble code that comes back within
3 engine starts (reset count 3 or less) is a ``Hard Fault''.
This means that the defect is there every time the
transmission control module checks that circuit.
SOFT FAULTS
A ``Soft Fault'' is one that occurs intermittently. It is
not there every time the transmission control module
checks the circuit. Most soft faults are caused by wiring
or connector problems. Intermittent defects must be
looked for under the specific conditions that caused
them.
LIMP-IN MODE
The transmission control module continuously
checks for electrical and internal transaxle problems.
When a problem is sensed, the transmission control
module stores a diagnostic trouble code. All but twelve
of these codes cause the transaxle to go into the
``Limp-in mode''. While in this mode, electrical power is
taken away from the transaxle. When this happens,
the only transaxle ranges that will function are:
Ä TRANSAXLE 21 - 145

(3) Remove the two aspirator mounting screws.
(4) Disconnect the aspirator intake hose from the
instrument panel. (5) Remove sensor/aspirator and it's wiring har-
ness from vehicle. To install, reverse the preceding operation.
WATER TEMPERATURE SENSOR
The water temperature sensor is located on the
heater core mounting plate (Fig. 17). This is a ther-
mistor which will pick up on the engines coolant
temperature. The computer control uses this informa-
tion to control the cold engine lockout time. The wa-
ter temperature sensor is not serviceable and must
be replaced if found to be defective. The Water Temperature Sensor is located on the
heater hose mounting plate between the heater hose
nipples.
REMOVAL AND INSTALLATION
(1) The A/C-heater housing assembly must be re-
moved for Water Temperature Sensor replacement.
Refer to Heater-A/C Unit Housing Removal and In-
stallationÐAC/AY Body for procedures. (2) Remove sensor mounting screw (Fig. 18).
(3) Disconnect the sensor pigtail wiring harness
from the main wiring harness and remove sensor
from vehicle. To install, reverse the preceding operation. When
tightening the sensor mounting screw, allow the sen-
sor to rotate and contact the upper heater hose nip-
ple. This will aid in sensor efficiency.
SUN SENSOR
The sun sensor (Fig. 19) is mounted on the driver
side of the vehicle on top of the instrument panel.
This is not a thermistor type sensor but rather a
photo diode. For this reason the sun sensor responds
to sun light intensity rather than temperature. It is
used to aid in determining proper mode door position.
The sun sensor is not serviceable and must be re-
placed if found to be defective.
REMOVAL AND INSTALLATION
(1) Carefully pry up the sensor from the instru-
ment panel with a screwdriver (Fig. 20). Place a rag
under the screwdriver to prevent scratching of the
instrument panel. (2) Disconnect the sensor at the wiring harness.
To install, reverse the preceding operation. Snap
the sensor securely to the instrument panel.
Fig. 16 In-Car Temperature Sensor/Aspirator Assembly Removal and Installation
Fig. 17 Water Temperature Sensor
Fig. 18 Water Temperature Sensor Removal and Installation
Ä HEATING AND AIR CONDITIONING 24 - 71

TORQUE REFERENCES
Individual Torque Charts appear at the end of many
Groups. Refer to the Standard Torque Specifications
and Bolt Identification Chart in this Group for torques
not listed in the individual torque charts (Fig. 4).
Torque specifications on the Bolt Torque chart are
based on the use of clean and dry threads. Reduce the
torque by 10% when the threads are lubricated with
engine oil and by 20% if new plated bolts are used. Various sizes of Torx head fasteners are used to
secure numerous components to assemblies. Due
to ever changing usage of fasteners, Torx head
fasteners may not be identified in art or text .
METRIC THREAD AND GRADE IDENTIFICATION
Metric and SAE thread notations differ slightly. The
difference is illustrated in Figure 5. Common metric fastener strength classes are 9.8
and 12.9 with the class identification embossed on
the head of each bolt (Fig. 6). Some metric nuts will
be marked with a single digit strength number on
the nut face.
SAE strength classes range from grade 2 to 8 with
line identification embossed on each bolt head. Mark-
ings corresponding to two lines less than the actual
grade (Fig. 7). For Example: Grade 7 bolt will exhibit
5 embossed lines on the bolt head.
METRIC SYSTEM
Figure art, specifications, and tightening references
in this Service Manual are identified in the metric
system and in the SAE system. During any maintenance or repair procedures, it is
important to salvage metric fasteners (nuts, bolts,
etc.) for reassembly. If the fastener is not salvage-
able, a fastener of equivalent specification should be
used.
Fig. 6 Metric Bolt Identification
Fig. 7 SAE Bolt Identification
Fig. 4 Grade 5 and 8 Standard Torque Specifica- tions
Fig. 5 Thread Notation (Metric and SAE)
6 INTRODUCTION Ä