Engine temperature warning on '07 4.8i

[eric giles]

I have run into an issue with the '07 4.8i I purchased a couple of weeks ago. It has happened twice-the first time I was in a friends driveway with the engine idling for about 5 to 7 minutes while showing them the X5, when the engine temperature warning came on the iDrive screen. I shut the engine off and left later on with no incident.

Then a few days later, I was in a drive thru line for 3 to 5 minutes and the warning came on again. I shut the engine off again until my order was ready, then started and drove off with no other issues.

From what I can tell, there only seems to be one electrically driven fan behind the radiator-no viscious coupled manual fan and not even an electrical fan in front of the A/C condenser. That seems to be a small amount of cooling for such a large engine that can generate a lot of heat.

My initial diagnosis is that the electrical fan isn't going into high speed mode when required-normally you would hear one kick in to this mode, but it never does on this vehicle. I have checked the coolant level and it is at the MAX mark in the reservoir.

Now whatever the issue is, it will be covered under warranty-but I was wondering if anyone else here has had this problem and what the issue might have been.