Seat Heaters

WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 2015 Jaguar XKR-S, 2015 Jaguar XKR, 2015 Jaguar XK, 2014 Jaguar XKR-S, and 2014 Jaguar XKR. However, it is still accessible from the selected car via links, so may be relevant.

There are 4 seat heater settings available; Off, 1, 2 or 3, which can be set through the TSD. The heat setting is relayed to the vehicle occupants through a graduated display on the TSD.

Operation of the heated seats is controlled by the ATC module. When the ATC module receives a heating request from the TSD, it broadcasts a message to the CJB over the medium speed CAN bus. The CJB then provides a hardwired 12 V supply to the 3 heater elements contained within each seat. The 3 heater elements, 2 in the seat cushion and 1 in the seat squab, are wired in series.

The ATC module monitors seat temperature using a temperature sensor located in each seat cushion. The CJB provides the temperature sensors with a 5 V supply. The level of the returned voltage back to the CJB is proportional to the seat temperature. The value of the return signal is broadcast to the ATC module over the medium speed CAN bus which it then converts into a temperature value to allow it to control seat temperature to the required level.

The ATC module will suspend or disable operation of the seat heaters if any of the following occur:

Battery voltage exceeds 16.5 ± 0.3 V for more than 5 seconds. Seat heating is re-enabled when battery voltage decreases to 16.2 ± 0.3 V
If a short or open circuit is detected
If the seat heat temperature rises significantly above the target temperature setting.

The graduated display on the TSD remains illuminated until the seat heaters are turned off or the engine stops. If the engine is restarted within 30 seconds the seat heater resumes the previous heating level.