mike75

Hi. My e270 cdi from 2004 driver seat heater only works when i am sitting on the seat. If i am get out of the car after a short period those 3 leds on the button go out. If i am go back into the car the seat heater works.

Is it normal?

despicable merc

Seems logical to me. Why heat when nobody in the seat.. Saves energy and heating components.

N_Jay

My 2007 seat heater automatically shuts off (one light at a time).
Are you sure it is not just timing out?

konigstiger

Heating element is built into seat cushion worst case scenario wiring may be damaged causing intermittent problem, check wiring/electrical connections.
http://workshop-manuals.com/mercedes...on/page_23909/

Plutoe

Depending on your VIN, the front seats will not heat up when the cabin temp is >55C.Plus if the interior temp is not available the outside temp is used as a backup!!

FYI the upper control module reads the switch command to heat the seats and to what stage.

Do yourself and all others a favor and get a quick test before you start tearing out the seats!!

PS: read your owners manual!!