INSTALLATION
(1) Position the seat switch onto the door trim
panel. Press into place ensuring all four clips are
engaged.
(2) Reconnect the wire harness connector to the
door module.
(3) Install the front door trim panel. Refer to the
Body section for the procedure.
(4) Reconnect the battery negative cable.
DRIVER POWER SEAT TRACK
DESCRIPTION
The power seat option includes a electrically oper-
ated power seat track and motor assembly. One seat
track assembly is located under each front seat. The
driver side power seat track also provides the mount-
ing location for the memory heated seat adjustable
pedal module on this vehicle. The lower half of the
power seat track is secured to the floor panel via four
studs and nuts that must be accessed from the
underside of the vehicle. Four bolts secure the bot-
tom of the seat cushion pan to the upper half of the
power seat track unit. Four additional bolts secure
the seat back frame to the power seat track unit.
The power seat track unit includes four reversible
electric motors that are secured to the upper half of
the track unit. Each motor moves the seat track
through a combination of worm-drive gearboxes and
screw-type drive units. Each of the power seat track
motors incorporates a integral position potentiometer,
which allows the memory heated seat adjustable
pedal module to monitor the motor position. This
enables the memory system to function by referenc-
ing the motor positions programmed into the module.
The front and rear of the seat are operated by two
separate vertical adjustment motors. These motors
can be operated independently of each other, tilting
the entire seat assembly forward or rearward; or,
they can be operated in unison by selecting the
proper power seat switch functions, which will raise
or lower the entire seat assembly. A third motor is
the horizontal adjustment motor, which moves the
seat track in the forward and rearward directions.
The forth motor is the recliner adjustment motor,
which moves the seat back in the forward and rear-
ward directions.
The power seat track unit cannot be repaired, and
is serviced only as a complete unit. If any component
in this unit is faulty or damaged, the entire power
seat track unit must be replaced.
OPERATION
When a power seat switch control knob is actuated,
a resistance signal is sent to the Driver Door Module
via hard wired connections. The driver door module
then sends the request to the Memory Heated Seat
Adjustable Pedal Module (MHSAPM) via the PCI
data bus circuit. The MHSAPM is responsible for the
12v battery feed and ground path to the power seat
track adjuster motor. The selected adjuster motor
operates to move the seat track or recliner through
its drive unit in the selected direction until the
switch is released, or until the travel limit of the
adjuster is reached.
DIAGNOSIS AND TESTING - DRIVER POWER
SEAT TRACK
The most reliable, efficient, and accurate means to
diagnose the power seat track requires the use of a
DRB III
t scan tool and the Diagnostic Procedures
information. The DRB III
t scan tool can provide con-
firmation that the PCI data bus is functional, that all
of the electronic modules are sending and receiving
the proper messages on the PCI data bus network,
and that the power seat system is receiving the
proper hard wired inputs and relaying the proper
hard wired outputs to perform its functions.
Following are tests that will help to diagnose the
hard wired components and circuits of the power seat
system.
PRELIMINARY TESTS
(1) Obtain a DRB III
t scan tool and check for any
stored diagnostic trouble codes recorded in the mem-
ory heated seat adjustable pedal module. Follow the
procedures called out in the proper diagnostic proce-
dures manual to resolve if codes are present.
(1) If any power seat is not operational in any
direction, check the power seat circuit breaker,
located in the Integrated Power Module. If OK, go to
Step 2. Refer to the Power Distribution section for
circuit breaker diagnosis and testing procedure.
(2) Check for proper battery or electrical system
voltage. The CS is equipped with a low-voltage cut-
off feature. If the electrical system voltage drops
below a predetermined set-point (approx. 11.5v), the
power seat system will not function until the proper
system voltage has been restored. If OK, go to Step
4. Refer to the Battery System and/or Charging Sys-
tem section for testing instructions.
(3) Obtain a DRB III
t scan tool and energize each
seat track motor axis one at a time. If any axis stops
without hitting the end of travel, the potentiometer
signal for that axis may have an open, short or be
mis-wired. Check the wiring to that axis (module to
motor). Fix any wiring problems and retry that axis.
If a certain seat track motor is inoperational, apply
12v and a good ground source to the inop motor. If
the motor does not operate in either direction replace
CS
POWER SEAT SYSTEM
8N - 29
DRIVER SEAT SWITCH (Continued)