And goes off when you turn the heated seat off again? Just one side or both? I'm thinking you should put up with a cold bum 'til you're got to the ahem bottom of it.
Since I never notice the warning light - signifying Mrs Doggy has left hers on again - I reckon you've got a more obvious indicator - look on it as a further bonus......
2002 HDi 2.2 Exec Estate, (2008-12) (wonderful)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)