Why is the "dummy gauge" a problem exactly? Modern cars don't even have coolant gauges, they have lights that come on when overheating.

The thing about the engines in the X5 is they all have electronically assisted thermostats. They will run hotter during low load and when idling to increase efficiency. The thermostat opens earlier when under high load to cool them down due to the increased heat being generated. As a result of this, the temperature swing is pretty drastic. In fact, the thermostat opening range varies from 80C - 103C and temperatures up to 110C are normal and perfectly fine.

When it is above normal operating temperature, the needle moves above TDC. When it is below normal operating temperature, the needle moves below TDC. This is a completely logical design. TDC encompasses the entire designed operating range of the engine.

There is no need and no benefit to watching the needle swing up and down. All it does is make people think they have a problem then they spend a lot of effort trying to make their car run cooler when it's actually running at the temperatures BMW designed it to.

"All my other cars have real temperature gauges!" - they also have normal thermostats
"I want to know when it's overheating or running hot" - it already does this, the needle moves above TDC if overheating

If you need to know the exact temperature for some reason (and there are some reasons to know this on occasion - and knowing the EXACT value in those cases is better than "the needle is here on the gauge") you can use the "secret cluster test" and display the numeric value.


This isn't a "fix" because it isn't a problem. It's change for changes sake.