My rear window heater is being automatically activated in our (texas) cold weather...15~20f.
Is this normal?
WJ

 

Yes it's normal. From the owners manual:The front (F) and rear (R or REAR) screen heaters may be switched on and off in any mode, including system off.

They will only operate when the engine is running.

The front screen heater switches off automatically after 6.5 minutes. The rear screen and door mirror heaters switch off automatically after 21 minutes.

The screen heaters can be manually deselected using the buttons.

In cold ambient conditions, at the start of a journey, the front and rear screen heaters will switch on automatically for the timed period. The rear heated screen will come on at temperatures below -1°C (30°F) and the front screen will come on below 5°C (41°F).

 

Thank you, another interesting feature of my jag.
wj