Module, Heated Seat (HSM): Operation

WARNING: This page is about a different car, the 2017 Dodge Charger. However, it is still accessible from the selected car via links, so may be relevant.

The Heated Seat Module (HSM) controls the heated seat system and the Heated Steering Wheel (HSW), when equipped. The HSM is secured to a mounting bracket located under the front passenger seat. The HSM responds to heated seat and steering wheel switch messages and ignition status inputs by controlling the 12 volt Direct Current (DC) output to the seat and steering wheel heating elements through high side drivers.

When either of the front heated seat switches in the U-Connect Touch™ screen module are pressed, the module sends a message over the Controller Area Network (CAN) data bus to the HSM, signaling the HSM to energize the heating elements for the front seat.

When the HSW switch in the U-Connect Touch™ screen module is pressed, the module sends a message over the Controller Area Network (CAN) data bus to the HSM, signaling the HSM to energize the heating element for the steering wheel.

The HSM energizes a high side driver to pulse width modulate the output to the heating elements. Heated seats turn off after approximately 45 minutes of continuous operation. If high-level heating is selected, the control system will remain at the high level for approximately 20 minutes and then drop to the low level. Normal heating cycle for the heated steering wheel is 52 minutes.

The heated seat and steering wheel system only operate when the engine is running. The heated seat and steering wheel system will turn off automatically whenever the ignition is set to any position other than Run.

The HSM is diagnosed using a scan tool and will automatically turn off the heating elements if it detects an open or low short in a heating element circuit. Refer to DIAGNOSIS AND TESTING .