Module, Heated Seat (HSM): Operation

WARNING: This page is about a different car, the 2020 Dodge Challenger. 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. The HSM is secured to a mounting bracket located under the front passenger seat that is attached to the seat pan. The HSM responds to heated seat switch requests, steering wheel switch requests 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 (HSD).

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.

The HSM energizes a HSD to Pulse Width Modulate (PWM) the output to the proper heating elements. The heated seats will turn off after approximately 45 minutes of continuous operation. If high-level heating is selected, the heated seat 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 will only operate when the engine is running. The heated seat 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 the HSM detects an open or low short in a heating element circuit. Refer to DIAGNOSTIC CODE INDEX .