System Description

Basic Control/Function 

The heated steering wheel switch turns on or off the heated steering wheel system. When the heated steering wheel switch is pressed, the switch sends on signals to the heated steering wheel control unit and turns on the heated steering wheel indicator. The heated steering wheel control unit controls outputs to the steering heater based on the heater temperature sensor values. While the heater is working, the heated steering wheel control unit receives the illumination signal via LIN, and adjusts the brightness of the indicator.

Automatic Control 

When the remote engine start control system is activated, the climate control system turns on the seat heater system based on the vehicle temperature. When the seat heater is turned on by the remote engine start control system, the gauge control module sends ON commands to the heated steering wheel control unit, and provides power to the heater pad. When the seat heater is turned on in this mode, the heated steering wheel indicator does not turn on.

Transition to Off State 

The heater output shall transition to the off state under any of the following conditions

• HTR +B power is off.
• The current operation state is off.
• Thermistor open/short failure is detected (DTC store).
• Heater current abnormal failure is detected (DTC store).
• Steering wheel not heating failure is detected (DTC store).
• Main heater switch failure is detected (DTC store).
• Heated steering wheel switch failure is detected.