temp gauge seems to take ages to get to running temp of 90c but heaters are red hot even when temp gauge is 60-70c doesnt show 90c until ive done nearly 12-13miles and sometimes it swings form 90 to 70 for couple secs the reaches 90c and stays stable and then maybe 20mins again does it again ?any ideas guys 

Hi Mine is the same takes ages for engine to get up to temp think that's just standard with diesel. And they have an aux heater which is why the air is hot but the engine isn't normally comes up on dash the yellow warning and says aux heater if that alert is set to show

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didnt think they all had aux heater cant understand why sometimes it drops temp even if been driving 1hr drops from 90c down to 60-70 then reads 90c again 

 

1 hour ago, Dennis the meance said:

didnt think they all had aux heater cant understand why sometimes it drops temp even if been driving 1hr drops from 90c down to 60-70 then reads 90c again 

 

I have a sneaky suspicion that mine does the same sometimes as the temperature of the air from the blowers can occasionally drop off for a while even though I'm doing motorway speeds.  At some point I'll get around to having Forscan monitor my morning commutes to see what it REALLY doing!

didnt think they all had aux heater cant understand why sometimes it drops temp even if been driving 1hr drops from 90c down to 60-70 then reads 90c again 
 

Mine dose this gets up to temp then I'll speed up or put heater on and temp drops a quarter and aux heater kicks back in

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Mine too, do 16 miles each way to work, then 100 miles of motorway home on a Friday and the gauge seems to hover around the 70 degree mark. Lost the company van in June, so didn't know whether it was driving in the winter that caused it? As the others say, the heater always works.