Durango RT 4WD V8-5.9L VIN Z LDC (2002)
Seat Heater Control Module: Description and Operation
Fig. 8 Heated Seat Module - Typical
HEATED SEAT MODULE
The heated seat module is located under the heated seat switches, where it is secured to a mounting bracket that is part of the center console. The
heated seat module has a single connector.
The heated seat module is an microprocessor designed to use inputs from the ignition switch, the two heated seat switches and the two heated seat
sensors to operate and control the heated seat elements in both front seats and the two heated seat indicator lamp Light-Emitting Diodes (LEDs) in
each heated seat switch. The heated seat module is also programmed to perform self-diagnosis of certain heated seat system functions and provide
feedback of that diagnosis through the heated seat switch indicator lamps.
The heated seat module cannot be repaired. If the heated seat module is damaged or faulty the entire module must be replaced.
The heated seat module operates on fused battery current received from the ignition switch. The module is grounded at all times through a
grounded to the drivers B-pillar. Inputs to the module include a resistor multiplexed heated seat switch request circuit for each of the two heated
seat switches and the heated seat sensor inputs from the seat cushions of each front seat. In response to those inputs the heated seat module
controls battery current feeds to the heated seat elements and sensors, and controls the ground for the heated seat switch indicator lamps.
When a heated seat switch request signal is received by the heated seat module, the module energizes the proper indicator lamp (Low or High) in
the switch by grounding the indicator lamp circuit to indicate that the heated seat system is operating. The heated seat module energizes the
selected heated seat sensor circuit and the sensor provides the module with an input indicating the surface temperature of the selected seat cushion.
The Low heat set point is about 38 °C (100.4 °F), and the High heat set point is about 42 °C (107.6 °F). If the seat cushion surface temperature
input is below the temperature set point for the selected temperature setting, the heated seat module energizes the heated seat elements in the
selected seat cushion and back. When the sensor input to the module indicates the correct temperature set point has been achieved, the module
de-energizes the heated seat elements. The heated seat module will continue to cycle as needed to maintain the selected temperature set point.
If the heated seat module detects a heated seat sensor value input that is out of range or a shorted or open heated seat element circuit, it will begin
flashing the High and/or Low indicator lamps in the affected heated seat switch. Refer to Heated Seat System for additional diagnosis and testing
procedures.
