Seats: Description and Operation
INTRODUCTIONPower seats can be adjusted in 8 different directions:
- Up or down
- Forward or back
- Tilt forward or rearward
- Recliner up or down
Two single armature permanent magnet reversible motors are coupled through cables to worm gear box assemblies. They are located in the seat tracks and upper supports. The two single gear motor assemblies attach to the seat tracks provide the various seat movements.
The electrical circuit is protected by a 20 amp circuit breaker located on the Junction Block and a 30 amp fuse in cavity H in the Power Distribution Center.
The power seat system is protected by a 20 amp circuit breaker located in cavity 23 of the junction block. This circuit breaker is HOT at all times. Circuit A3 is the power supply for the circuit breaker.
The A3 circuit originates in the Power Distribution Center (PDC) and is protected by a 30 amp fuse located in cavity H. This circuit is also the feed for the Daytime Running Lamps, Headlamp Relay, and Power Door Locks.
Circuit F35 is the feed for the switches and the seat motors from the circuit breaker. A BUS bar internal to the switches feeds all the contacts. Grounding for the seats is provided on circuit Z1, which terminates at the instrument panel left side cowl.
CIRCUIT OPERATION
Driver's Seat
When the operator selects the FRONT VERTICAL UP function, power is passed on the F35 circuit through the CLOSED contacts in the switch to the P19 circuit. The P19 circuit connects to the motor. Ground is provided on the P21 circuit back to the switch. A ground BUS bar internal to the switch then connects to the Z1 circuit.
For FRONT VERTICAL DOWN function the circuits are reversed. P21 is the feed, and P19 is the ground.
When the operator selects the HORIZONTAL FORWARD function, power is passed on the F35 circuit through the CLOSED contacts in the switch to the P15 circuit. The P15 circuit connects to the motor. Ground is provided on the P17 circuit back to the switch. A ground BUS bar internal to the switch then connects to the Z1 circuit.
For HORIZONTAL REARWARD function the circuits are reversed. P17 is the feed, and P15 is the ground.
When the operator selects the REAR VERTICAL UP function, power is passed on the F35 circuit through the CLOSED contacts in the switch to the P11 circuit. The P11 circuit connects to the motor. Ground is provided on the P13 circuit back to the switch. A ground BUS bar internal to the switch then connects to the Z1 circuit.
For REAR VERTICAL DOWN function the circuits are reversed. P13 is the feed, and P11 is the ground.
When the operator selects the RECLINE REAR-WARD function, power is passed on the F35 circuit through the CLOSED contacts in the switch to the P41 circuit. The P41 circuit connects to the motor. Ground is provided on the P43 circuit back to the switch. A ground BUS bar internal to the switch then connects to the Z1 circuit.
For RECLINE FORWARD function the circuits are reversed. P43 is the feed, and P41 is the ground.
Passenger's Seat
When the operator selects the FRONT VERTICAL UP function, power is passed on the F35 circuit through the CLOSED contacts in the switch to the P18 circuit. The P18 circuit connects to the motor. Ground is provided on the P20 circuit back to the switch. A ground BUS bar internal to the switch then connects to the Z1 circuit.
For FRONT VERTICAL DOWN function the circuits are reversed. P20 is the feed, and P18 is the ground.
When the operator selects the HORIZONTAL FORWARD function, power is passed on the F35 circuit through the CLOSED contacts in the switch to the P14 circuit. The P14 circuit connects to the motor. Ground is provided on the P16 circuit back to the switch. A ground BUS bar internal to the switch then connects to the Z1 circuit.
For HORIZONTAL REARWARD function the circuits are reversed. P16 is the feed, and P14 is the ground.
When the operator selects the REAR VERTICAL UP function, power is passed on the F35 circuit through the CLOSED contacts in the switch to the P10 circuit. The P10 circuit connects to the motor. Ground is provided on the P12 circuit back to the switch. A ground BUS bar internal to the switch then connects to the Z1 circuit.
For REAR VERTICAL DOWN function, the circuits are reversed. P12 is the feed, and P10 is the ground.
When the operator selects the RECLINE REAR-WARD function, power is passed on the F35 circuit through the CLOSED contacts in the switch to the P42 circuit. The P42 circuit connects to the motor. Ground is provided on the P44 circuit back to the switch. A ground BUS bar internal to the switch then connects to the Z1 circuit.
For RECLINE FORWARD function the circuits are reversed. P44 is the feed, and P42 is the ground.