"CHECK COOLANT LEVEL"-???
 

2005 X5 3.0i

"CHECK COOLANT LEVEL" came on yesterday so I assumed it was low again. When I checked it, it was at MAX indicated by the dipstick. So just to be sure, I added tiny bit more but the warning still comes on. What do I do?

If the fluid is actually to the correct level, then it may be a faulty coolant level sensor.

Is that something easily replaceable or do I have to get it done at the dealer?

Hard to say not knowing what you are able or capable of doing. Wasn't hard on my e36, but haven't needed to change it out on my X, so I am not sure. Best bet is to search for coolant level sensor threads and then make a decision.

Very easy to change out the sensor. 5 mins max. prob a faulty sensor.

Can it be done from the top or do I have to crawl under the engine to replace this?

Coolant sensor is at the bottom of coolant reservoir. Unscrew reservior, don't disconnect hoses, turn it, so you found see or feel sensor on the bottom ( blue color sensor, near bottom hose). Pull it out and replace with new one. Start engine.

Would the coolant spill out when doing this?

Its possible, but no worries, you can cover it with your finger.

Just curious, would that be item 8 here?

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