Thanks for replies... Interesting that I dropped out the front fuse box and found that even when I remove the relays and operate the switch for the heated screen I still hear a click ... I reckon the relay is embedded in the front fuse box.

Any BMW tech's out there that can confirm or clarify ...

So I noticed during the cold spell the rear heated screen wasn't good and today running some diag on another problem I found an error in the logs saying the relay is faulty. Great but where on earth is it ... I have searched this car high and low and I cannot find it or any reference to it.

Fuse ...

Ok so bit of an update.. I found how to use the INPA software and managed to check all of the heater/air circulation flaps are working fine. Also found the heater core sensors and they both report approx the same temp (1 degree off ) so all operations of the heating system check out ok... But i did ...

Hi Thanks for the reply. I have cleaned out the front sensor but still no good. But I have got the BMW diag software so I plugged this in and it told me I have a sensor error, which I think is the right hand heater core sensor.

To check I cleared all the errors and used the car for a few days so ...

Couldn't wait until tomorrow and a bit bored so took out IKHA earlier .. as suggested a bit dusty and the remains of an old insect.. so cleaned out the thin bar sensor and the small fan ... plugged back in and checked fan was running which it was...but still no good.

What seems strange is the fact ...

Thanks , I like your confidence, but I am sure you are right as it will get hot on both sides its more the control of that heat I think.... 

Going to remove IKHA tomorrow and check so I will let you know

Thank you very much for taking the time to reply

Hi thanks.. I did find the poll thing strange but it wanted those before I could post !!! Will know for next time.

Any way will take a look at this as I had the same thing on my old E53 ... but I didn't know if the E70 had the same so will take a look.

If its not that I might have to buy a new ...

Hi, New to this forum so hopefully somebody knows about this and maybe some of what I mention might help others. My E70 (2007) seems to have a mind of its own when it comes ot heating or climate control. To get any heat I have to set the temp to full (28) on each side.. if I reduce to 27 it goes ...