Bosch KGU30604GB Freezer compartment too warm

[Barrie]

Hi,
I have a Bosch frost free fridge freezer KGU30604gb that used to work fine now the fridge is ok but freezer part seems to get too warm and defrosts some food in it. I have replaced the freezer fan motor but no good. It seems to freeze things down then at times just warms up and will defrost a couple of items in teh freezer. at times the machine also seems to pulse and with each pulse it sounds like either the fam or compressor is trying to kick in and all the indicator lights on the display panel flash on then off with each pulse. This goes for a few times then reverts back to having normal lights on. The temp warning light also comes on some of the time and when pressing the "super" button to engage fast freeze the light on teh button comes on but the machine does nothing else.

Any suggestions as to what this may be?

Hope someone has an idea

Thanks

Barrie