Chrysler 1998 Voyager Service Manual page 1548

21 - 74 TRANSAXLE AND POWER TRANSFER UNIT
DESCRIPTION AND OPERATION (Continued)
TORQUE MANAGEMENT
Most 41TE transaxles utilize torque management.
Torque management is a unique function of the Pow-
ertrain Control Module (PCM). The PCM receives
output signals from the Transmission Control Module
(TCM) and many various engine sensors. The PCM
evaluates these signals and decides if it is necessary
to decrease the output of the engine's torque. This
reduction in torque does not interfere with the nor-
mal operation of the vehicle. This reduction in torque
will prolong the life of the drivetrain components.
Torque reduction is not noticeable in normal driving
functions. The torque reduction function shuts off
above 16 MPH.
ON-BOARD DIAGNOSTICS
This vehicle utilizes a diagnostic system called
OBDII. The powertrain control module communicates
with the Transmission Control Module. Whenever
the transaxle sets a fault in the Transmission Con-
trol Module (dependent on which fault is set), the
powertrain control module will turn on a MIL (Mal-
function Indicator Lamp) on the instrument cluster.
By reading the code in the powertrain control module
it will tell you where the fault occurred. If the fault
occurred in the transaxle, the controller will read a
CODE 45. For further information regarding OBDII,
refer to Group 25, Emission Systems.
These controls provide comprehensive, on-board
transaxle diagnostics. The information available can
aid in transaxle diagnosis. For example, apply ele-
ment buildup rate indicates solenoid performance.
Also included are self diagnostic functions. Self diag-
nostics allow the technician to test the condition of
the electronic controls. The Transmission Control
Module continuously monitors its critical functions. It
also records any malfunctions, and the number of
engine starts since the last malfunction. This allows
the technician to use the information in the event of
a customer complaint.
TRANSMISSION CONTROL MODULE
Do not interchange Transmission Control Modules
with previous year transmission control modules. If a
same year TCM is being used from a different vehi-
cle, the following procedures must be performed:
• Quick Learn Procedure
• Electronic Pinion Factor Procedure
The Transmission Control Module is located on the
right inner fender panel, in the engine compartment.
It is held in place by four mounting screws.
NOTE: If the Transmission Control Module has
been replaced, the following procedures must be
performed:
• Quick Learn Procedure: This procedure will
allow the transmission control module to learn the
characteristics of the vehicle.
• Electronic Pinion Factor Procedure: This proce-
dure will reprogram the TCM to compensate for dif-
ferent tire sizes and final drive ratios.
GEARSHIFT AND PARKING LOCK CONTROLS
The transaxle is controlled by a lever type gear-
shift incorporated within the steering column. The
control has six selector lever positions: P (park), R
(reverse), N (neutral), and D (drive), 2 (second), and
1 (first). The parking lock is applied by moving the
selector lever past a gate to the P position. Do not
apply the parking lock until the vehicle has
stopped; otherwise, a severe ratchet noise will
occur.
TRANSMISSION RANGE SENSOR
The 41TE transaxle is equipped with a transmis-
sion range sensor that is located on top of the valve
body. This sensor will allow for accurate transmission
gear position measurement.
To service the transmission range sensor (TRS),
you must remove the valve body. For repair proce-
dures, refer to the Removal and Installation section
within this group.
Also located within the TRS is a transmission tem-
perature sensor. This sensor is used to measure the
transmission fluid sump temperature. The transmis-
sion temperature sensor is serviced with the TRS as
a unit.
SHIFT POSITION INDICATOR
The shifter position indicator is located in the
instrument cluster. The shifter position indicator out-
lines with a box the gear position the transaxle man-
ual valve lever is in.
The transmission range sensor (located on the
valvebody) sends a signal to the TCM on the position
of the transaxle manual valve lever. The TCM
receives the switch signal and processes the data.
The TCM sends the Shift Lever Position (SLP) infor-
mation to the BCM via the CCD bus. The BCM then
outlines with a box the appropriate shifter position
indicator in the instrument cluster.
To replace the shifter position indicator, refer to
Group 8E, Instrument Panel And Gauges.
NS