Seats: Description and Operation

INTRODUCTION
A six-way driver side power seat is an available factory-installed option for this model, when it is also equipped with the split bench seat option. Extended cab (club cab and quad cab) versions equipped with the power seat option also have a driver side power lumbar support feature.

Power Seat System
The power seat system option allows the driver to electrically adjust his seating position for optimum control and comfort using the power seat switches located on the outboard seat cushion side shield. 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 Power Distribution Center and a circuit breaker in the junction block, regardless of the ignition switch position.

Extended cab (club cab and quad cab) models equipped with the power seat option also feature a power operated lumbar support in the driver side seat back. The power lumbar support allows the driver to inflate or deflate a bladder located in the lower seat back to achieve optimum comfort and support in the lower lumbar region of the spinal column. The power lumbar support shares the battery feed circuit of the power seat system.

The power seat system includes the power seat adjuster and motors unit, the power lumbar support bladder and electric pump (extended cab only), the power seat switch, and the circuit breaker. Following are general descriptions of the major components in the power seat system. Refer to the owner's manual in the vehicle glove box for more information on the features, use and operation of the power seat system.

SYSTEM OPERATION
Power Seat Switch
The power seat in standard cab models can be adjusted in six different ways using the power seat switch. The power seat switch for extended cab models (club cab and quad cab) has an additional switch knob for adjusting the power lumbar support. The switch is located on the lower outboard side of the driver side seat cushion on the seat cushion side shield on all models. Refer to the owner's manual in the vehicle glove box for more information on the power seat switch functions and the seat adjusting procedures.

The individual switches in the power seat switch module cannot be repaired. If one switch is damaged or faulty, the entire power seat switch module must be replaced.

Power Seat Adjuster And Motors
There are three reversible motors that operate the power seat adjuster. The motors are connected to worm-drive gearboxes that move the seat adjuster through a combination of screw-type drive units.

The front and rear of a seat are operated by different motors. They can be raised or lowered independently of each other. When the center seat switch is pushed in the Up or Down direction, both the front and rear motors operate in unison. On standard cab models the entire seat is moved up or down, on extended cab models (club cab and quad cab) the seat cushion moves independently of the seat back in the up or down directions. The forward-rearward motor is operated by pushing the center seat switch in the Forward or Rearward direction, which moves the entire seat in the selected direction on all models.

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

Each motor contains a self-resetting circuit breaker to protect it from overload. Consecutive or frequent resetting of the circuit breakers must not be allowed to continue, or the motors may be damaged. Make the necessary repairs.

The power seat adjuster and motors cannot be repaired, and are serviced only as a complete unit. If any component in this unit is faulty or damaged, the entire power seat adjuster and motors assembly must be replaced.

Power Lumbar Adjuster And Motor
There is a reversible motor that operates the power lumbar adjuster. The motor is connected to a pump that inflates or deflates the rubber lumbar adjuster bladder unit.

When the power lumbar switch is actuated, a battery feed and a ground path are applied through the switch contacts to the motor. The motor operates to move the pump in the selected direction until the switch is released, or until the inflation limit of the lumbar bladder 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 motor to run in the opposite direction, and the pump deflates the bladder.

The motor contains a self-resetting circuit breaker to protect it from overload. Consecutive or frequent resetting of the circuit breaker must not be allowed to continue, or the motor may be damaged. Make the necessary repairs.

The power lumbar adjuster and motor cannot be repaired, and are serviced only as a complete unit. If any component in this unit is damaged or is faulty, the entire power lumbar adjuster and motor unit must be replaced.

Circuit Breaker
An automatic resetting circuit breaker in the junction block is used to protect the power seat system circuit. The circuit breaker can protect the system from a short circuit, or from an overload condition caused by an obstructed or stuck seat adjuster.

The circuit breaker cannot be repaired and, if faulty or damaged, it must be replaced.