Principles of Operation
Seats
Principles of Operation
Driver and Passenger Power Seats Without Memory
The 10-way power seat feature (driver seat only) moves the seat in 10 possible directions: the seat can be moved forward or backward and the front and back of the cushion can be moved up and down independently. The backrest of the seat can be moved forward and backward, and the lumbar in and out. All 10 positions are controlled by one switch. The power seat feature operates independent of the position of the ignition.
The 6-way power seat feature moves the seat in 6 possible directions: the seat can be moved forward or backward and the front and back of the cushion can be moved up and down independently. The power seat feature operates independent of the position of the ignition.
The power seat motors are hardwired to the seat control switch. The circuits are normally at ground through the seat control switch. An individual circuit is switched to voltage when a specific adjustment position is selected.
Power Driver Seat With Memory
NOTE: A memory recall can be initiated only if the vehicle is in PARK or NEUTRAL gear and the ignition switch is not in START. A memory recall in progress will not be affected by moving the ignition switch to START or by moving the gearshift lever out of PARK or NEUTRAL.
The driver power memory seat is controlled by the Driver Seat Module (DSM). The memory seat feature allows the driver to program a personalized seat position that can be recalled using the memory switch or a Remote Keyless Entry (RKE) transmitter. There are 2 memory settings possible. The adjustable pedal (if equipped) positions are also stored and recalled with the driver memory seat positions.
The driver seat control switch provides voltage to the DSM when activated. The NEUTRAL position of each driver seat control switch position is a ground state through the seat control switch contacts. A voltage input causes the DSM to power the appropriate motor until the input is removed. Ground is the normal state of the motor circuits through the DSM and is not switched to control the motors. The DSM internally switches the appropriate circuit from ground to voltage for operating the motors.
As the seat is adjusted, the DSM constantly monitors the motor position sensors to record the current seat position. The DSM will remove voltage from the motor upon termination of the seat control switch input or if the DSM does not see movement from the motor by monitoring the position sensor.
The DSM communicates DTC and other information using the Medium Speed Controller Area Network (MS-CAN) communication bus. It should be noted for diagnostics that because Controller Area Network (CAN) bus communication is more robust and reliable than other methods, it may be possible to have limited module communication with one of the CAN bus circuits disconnected or shorted to ground. Refer to Information Bus for information concerning MS-CAN bus communication.
Easy Entry/Easy Exit
The easy entry/easy exit feature moves the driver seat backwards about 50.8 mm (2 in) when the ignition key is removed from the ignition switch. The DSM receives a key out command over the MS-CAN communication network and powers the driver seat rearward. This function will not operate if the seat is less than the 50.8 mm (2 in) travel distance to the end of the track or the function has been disabled. The DSM will also cancel this operation if a valid input command is received from the driver seat control switch, memory SET switch or exterior mirror control switch.
The DSM will record the current driver seat positions before powering the seat for an easy exit operation. This recorded position will be used to return the driver seat to this position on the easy entry operation. During easy entry operation, the seat is returned to the position previous to the easy exit operation.
The easy entry/easy exit feature can be enabled/disabled using a scan tool. When enabled, the feature becomes a user accessible item on the message center allowing the user to turn the feature on and off. Refer to the Owner's Literature or Instrument Panel, Gauges and Warning Indicators for information on the message center.
Heated Seats
The driver and passenger heated seats share a common ignition and battery feed to the heated seat control switch assembly. The ignition feed supplies voltage to the logic board and illumination of the heated seat switch assembly and the battery feed is used to provide voltage to the heater mats. The heated seat switch assembly uses a shared ground for the logic board and illumination.
When a heated seat switch is pressed with the ignition switch in RUN or START, a momentary ground is provided to the logic board of the heated seat switch assembly. The logic board then activates an internal relay in the heated seat switch assembly that provides voltage to a bi-metallic thermostat that is part of the seat cushion heater mat.
The driver seat cushion and backrest heater mats are wired in series as are the passenger seat cushion and backrest heater mats. The heated seat system is designed to maintain the temperature by the opening (no voltage to the heated seat mats) and closing (voltage supplied to the heated seat mats) of the bi-metallic thermostat.
The heated seat will remain ON until the heated seat switch is pressed or until ignition voltage is removed from the heated seat switch assembly.
Normal heat cycle may require several minutes to initially warm the seat. The seat should be occupied to correctly test for normal operation. Temperature measuring devices do not provide an accurate method for testing heated seat operation as surface temperatures are subject to human and environmental characteristics. Correct testing requires heater mat resistance measurements which have tight tolerances affecting the length of time for the heater mats to reach maximum operating temperature.
Second Row 60/40 E-Z Entry Seats
The 7-passenger second row E-Z entry seat backrest will:
- recline to 5 different positions.
- To recline either the 60 percent or the 40 percent backrest, while sitting in the seat, turn the recliner handle and push back to the desired position. With the backrest adjusted, release the recliner handle and the backrest will stay where positioned. To return the backrest, turn the recliner handle and allow the backrest to come forward with the spring load of the recliners.
- fold down.
- NOTE: Make sure that the head restraint is in the down position and no objects such as books, purses or briefcases are on the floor in front of the second row seats before folding the backrest down.
NOTE: The backrest cannot be returned to the upright (vertical) position until the kneeling mechanism is returned to the standing (upright) position and the latch feet assembly is latched to the mounting plate strikers.
To fold down either the 60 percent or the 40 percent seat backrest, lower the head restraint by pulling on the release strap. Turn the recliner handle or pull the third row occupant release strap and fold the backrest forward and down until it lays flat. To return the seat backrest to the upright (vertical) position, lift and pivot the top of the backrest toward the rear of the vehicle, rotating the backrest until you hear a click, locking it in the upright (vertical) position. Make sure the seat backrest is locked in position.
The 7-passenger, second row E-Z entry seats can be positioned in 2 functional positions. The E-Z entry seat will:
- kneel to create a level cargo area (load floor) after the backrest has been folded down.
- NOTE: To kneel the seat, the backrest must be folded forward and all the way down. Remove anything between the backrest and cushion that may prevent the backrest from folding all the way down.
The front legs of the seat will pivot forward and lower (kneel) the seat creating a level load floor with the rear cargo area of the vehicle. Fold the backrest forward and all the way down. Lift the kneeling mechanism release handle in the back of the backrest and moderately push the seat forward and down into the kneel position. To stand the seat back up from the load floor position, lift up with moderate force at the front of the seat cushion frame, pivot the seat up and toward the rear of the vehicle until the kneeling mechanism is locked in place. Make sure the kneeling mechanism is locked in position by pushing the seat forward and down. Lift and pivot the top of the backrest toward the rear of the vehicle, rotating the backrest until you hear a click, locking it in the upright (vertical) position. Make sure the seat backrest is locked in position.
- fold up out of the way (E-Z entry position), after the backrest has been folded down, to allow access to the third row seats through the second row doors.
- NOTE: To release the latch feet from the mounting plate strikers and position the seat to the E-Z entry position, the backrest must be folded forward and all the way down. Remove anything between the backrest and cushion that may prevent the backrest from folding all the way down.
NOTE: The recliner handle or third row occupant release strap must be released once the backrest is folded down then actuated a second time to release the seat from the mounting plate strikers.
Fold the backrest forward and down. Once the backrest is positioned down, release the recliner handle or third row occupant release strap. Turn the recliner handle or pull the third row occupant release strap a second time until the seat releases from the mounting plate strikers. Lift up on the rear of the seat, pivoting it forward, away from the third row seats and up to the E-Z entry position. To return the seat, push the rear of the seat down with moderate force to latch the seat to the mounting plate strikers. Make sure the seat is latched to the mounting plate strikers by lifting up on the rear of the seat. Lift and pivot the top of the backrest toward the rear of the vehicle, rotating the backrest until you hear a click, locking it in the upright (vertical) position. Make sure the seat backrest is locked in position.
Third Row Power-Fold Seat
NOTICE: To prevent possible damage to the third row seat or the safety belts, make sure that the safety belts are not fastened when moving the seat to the load floor position.
NOTICE: Make sure that no objects such as books, purses or briefcases are on the floor in front of the third row seats or on the seat cushion before lowering the backrest(s) or the seat may not fold all the way down.
NOTE: The Smart Junction Box (SJB) may also be identified as the Generic Electronic Module (GEM).
For the third row power-fold seat to operate, a shared ground is supplied by the SJB to both of the power-fold seat relays, enabling the seats to then be moved by pressing one of the third row power-fold seat control switches. The third row power-fold seat operates only when the vehicle is in PARK and the liftgate glass or liftgate door are open.
The third row power-fold seat relays will be provided ground on the coil side from the SJB for 30 minutes when the transmission selector is in PARK, and the liftgate, or liftgate glass is open. The ground will be disabled 30 minutes after turning the vehicle OFF. If the ground is disabled after 30 minutes, the ground can be enabled by opening any door, pressing the unlock key on the key fob, pressing any keyless keypad button or turning the ignition key.
The third row power-fold seat motors transfer movement to a drive screw and bracket assembly to raise and lower the seat backrest and cushion.