That is not the "temp gauge" but the external temp gauge. It probably needs replaced, you can buy the part and do it yourself. If is usually located behind the front air dam, on most BMW's. If not a dealer or independent shop could change it for you.

__________________

An unwavering defender of those I see worth protecting.

"promote the general welfare, not provide the general welfare"

We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.