Pacifica V6-3.8L VIN L (2005)
Seat Heater Switch: Description and Operation
Front Heated Seat Switch
CS Driver Heated Seat Switch
The heated seat switch assemblies are mounted in the left and right side front door trim panels. One switch assembly is used for each front heated seat.
The two momentary position switches, are incorporated into one large switch assembly that also includes other switches. The drivers side switch
assembly includes the memory, heat and power seat switches as well as the adjustable foot pedal switch. The passenger side switch assembly includes the
power seat and heated seat switches only. The heated seat switches provide a resistive multiplexed signal to the appropriate Door Module through
separate hard wired circuits. Each switch has an Low and High position so that both the driver and the front seat passenger can select a preferred seat
heating level. Each switch has two Light-Emitting Diodes (LED) which light to indicate that the heater for the seat is turned on.
The heated seat switches and their LEDs cannot be repaired. If either switch or LED is faulty or damaged, the entire switch assembly must be replaced.
There are two momentary positions that can be selected with each of the heated seat switches, Low and High. When the switch closest to the
driver/passenger is depressed, the Low position is selected and the "LO" position LED indicator illuminates. When the switch farthest from the
driver/passenger is depressed, the High position is selected and the "HI" position LED indicator illuminates. If the switch is depressed a second time in
the same direction, Off is selected and both LED indicators are extinguished.
Both heated seat switch assemblies provide separate resistive multiplexed inputs to the appropriate door module. The Door Module then sends a PCI
Data Bus message to the Memory Heated Seat Adjustable Pedal Module (MHSAPM) to indicate the selected switch position. The module responds to
the heated seat switch messages by controlling the 12v output to the front seat heating elements. The Low heat position set point is about 35° C (97° F),
and the High heat position set point is about 40° C (105° F).