The power seat system allows the driver and front seat passenger to electrically adjust their seating positions using
the power seat switches located on the outboard seat cushion side shield of each front seat. The power seat system
allows the seating position to be adjusted forward, rearward, front up, front down, rear up, or rear down. The power
seat system receives battery current through a fuse in the Integrated Power Module, regardless of the ignition
switch position. The power seat system includes the following components:

•

Driver Power Seat Switch

•

Passenger Power Seat Switch

•

Driver Power Seat Track

•

Passenger Power Seat Track

Some models equipped with the power seat option also feature a manually operated lumbar support in the seat
back. The lumbar support allows the user to adjust lower seat back pressure to achieve optimum comfort and sup-
port in the lower lumbar region of the spinal column. The lumbar support is controlled by a knob on the outboard
side of the seat back assembly.

OPERATION

The power seat system receives battery current through a 50 amp fuse in the Power Distribution Center (PDC) so
that the power seats remain operational, regardless of the ignition switch position.

When a power seat switch is actuated, a battery feed and a ground path are applied through the power seat switch
contacts to the appropriate motor or motors. The motor and drive unit operate to move the seat in the selected
direction until the switch is released, or until the travel limit of the power seat track is reached. When the switch is
moved in the opposite direction, the battery feed and ground path to the motor is reversed through the switch con-
tacts. This causes the motor to run in the opposite direction.

DIAGNOSIS AND TESTING

POWER SEAT SYSTEM

Before any testing of the power seat system is attempted, the battery should be fully-charged and all wire harness
connections and pins checked to ensure proper continuity and grounds. Also ensure that the seat being diagnosed
is not jammed by foreign material. With the dome lamp on, apply the power seat switch in the direction of the
concern. If the dome lamp dims, the seat may be jamming. Check under and behind the seat for binding or obstruc-
tions. If the dome lamp does not dim, proceed with testing of the individual components and circuits.

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POWER SEATS - SERVICE INFORMATION

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For complete circuit diagrams, refer to the appropriate wiring information. The wiring information includes wir-
ing diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector
pin-out information and location views for the various wire harness connectors, splices and grounds.

Operate the power seat switch and move the seat in all directions. The seat should move in each of the selected
directions.

If the power seat adjuster fails to operate in more than one direction, proceed as follows:

1. Inspect the power seat adjuster motors to ensure the electrical connectors are fully seated to the motors. If OK,

go to Step 2. If not OK, connect the electrical connector to the fully seated position.

2. Check the power seat fuse in the integrated power module. If OK, go to Step 3. If not OK, repair the circuit as

necessary and replace the inoperative fuse.

3. Remove the power seat switch from the seat cushion side panel. Check for battery voltage at the fused B(+)

circuit cavity of the power seat switch wire harness connector. If OK, go to Step 4. If not OK, repair the open
circuit to the integrated power module as required.

4. Check for continuity between the ground circuit cavity of the power seat switch wire harness connector and a

good ground. There should be continuity. If OK, go to Step 5. If not OK, repair the open circuit to ground as
required.

(Refer to 8 - ELECTRICAL/POWER SEATS/SEAT SWITCH - DIAGNOSIS AND TESTING). If the switch tests

OK, check the wire harness between the power seat switch and the motor. If the circuits check OK, replace the
inoperative power seat adjuster assembly. If the circuits are not OK, repair the wire harness as required.

POWER SEAT TRACK

DESCRIPTION

The eight-way power seat option includes a power
seat track assembly (1) located under each front seat.
The power seat track assembly replaces the standard
manually operated seat tracks. The lower half of the
power seat track is secured at the front with two bolts
to the floor panel seat cross member, and at the rear
with two bolts to the floor panel. Four nuts secure the
bottom of the seat cushion frame to the upper half of
the power seat track unit.

The power seat track assembly cannot be repaired,
and is serviced only as a complete assembly. If any
component in this assembly is inoperative or dam-
aged, the entire power seat track must be replaced.

OPERATION

The power seat track unit includes three reversible electric motors that are secured to the upper half of the track
unit. Each motor moves the seat adjuster through a combination of worm-drive gearboxes and screw-type drive
units.

The front and rear of the seat are operated by two separate vertical adjustment motors. These motors can be oper-
ated 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. The
third motor is the horizontal adjustment motor, which moves the seat track in the forward and rearward directions.

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POWER SEATS - SERVICE INFORMATION

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DIAGNOSIS AND TESTING

POWER SEAT TRACK

Operate the power seat switch to move all three seat motors in each direction. The seat should move in each of the
selected directions. If the power seat track fails to operate in only one direction, move the seat track a short dis-
tance in the opposite direction and test again to be certain that the track is not at its travel limit. If the power seat
track still fails to operate in only one direction, (Refer to 8 - ELECTRICAL/POWER SEATS/DRIVER SEAT SWITCH
- DIAGNOSIS AND TESTING) for power seat switch diagnosis. If the power seat track fails to operate in more than
one direction, proceed as follows:

1. Check the power seat fuse in the integrated power module. If OK, go to Step 2. If not OK, repair the circuit as

necessary and replace the inoperative fuse.

2. Remove the power seat switch from the seat. Check for battery voltage at the fused B(+) circuit cavity of the

power seat switch wire harness connector. If OK, go to Step 3. If not OK, repair the open circuit to the integrated
power module as required.

3. Check for continuity between the ground circuit cavity of the power seat switch wire harness connector and a

good ground. There should be continuity. If OK, go to Step 4. If not OK, repair the open circuit to ground as
required.

4. Test the power seat switch, (Refer to 8 - ELECTRICAL/POWER SEATS/DRIVER SEAT SWITCH - DIAGNOSIS

AND TESTING). If the switch tests OK, check the wire harness between the power seat switch and the motor for
shorts or opens. If the circuits check OK, replace the inoperative power seat track (adjuster) assembly. If the
circuits are not OK, repair the wire harness as required.

REMOVAL

1. Remove the appropriate seat from the vehicle. (Refer to 23 - BODY/SEATS/SEAT - REMOVAL).

2. Remove the power seat switch from the seat. (Refer to 8 - ELECTRICAL/POWER SEATS/DRIVER SEAT

SWITCH - REMOVAL).

3. Remove four seat track mounting nuts from cushion pan.

4. Disconnect the power seat electrical connectors and remove the seat track from the seat cushion.

5. Remove the necessary components that must be transferred to the replacement seat track (seat belt buckles,

wire harness, etc.).

INSTALLATION

1. Install the necessary components that must be transferred to the replacement seat track (seat belt buckles, wire

harness, etc.).

2. Position the seat track and install the retaining nuts on the seat cushion pan studs. Torque the bolts to 25 N·m.

3. Route and connect the power seat electrical connectors on the seat track and cushion pan.

4. Install the power seat switch on the seat. (Refer to 8 - ELECTRICAL/POWER SEATS/DRIVER SEAT SWITCH -

INSTALLATION).

5. Install the seat in the vehicle (Refer to 23 - BODY/SEATS/SEAT - INSTALLATION).

6. Connect the battery negative cable.

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POWER SEATS - SERVICE INFORMATION

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SWITCH-POWER SEAT

DESCRIPTION

The power seats on this vehicle can be adjusted in
eight different directions, up, down, front up, front
down, rear up, rear down, rearward and forward. The
power seat switch is located on the outboard side of
the seat cushion on the seat cushion side shield.

The individual switches in the power seat switch
assembly cannot be repaired. If one switch is dam-
aged or inoperative, the entire power seat switch
assembly must be replaced.

OPERATION

When a power switch control knob or knobs are actuated, a battery feed and a ground path are applied through the
switch contacts 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. When the switch is moved in the opposite direction, the battery feed and ground path to the
motor are reversed through the switch contacts. This causes the adjuster motor to run in the opposite direction.

No power seat switch should be held applied in any direction after the adjuster has reached its travel limit. The
power seat adjuster motors each contain a self-resetting circuit breaker to protect them from overload. However,
consecutive or frequent resetting of the circuit breaker must not be allowed to continue, or the motor may be
damaged.

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