Have a strange case on my XF 2011, the coolant warning never shows up & every other next day I am seeing the coolant level goes way below the minimum.

I opened the rack below, and found no visible leaks. It was dry. The hose pipe do not have any cracks either. I am mixing 50:50 ratio of Jag Coolant with Water.

Getting tired of filling the coolant every morning now, I am topping up every time I see it goes way below minimum. Is there any solution to this, I am sure being an old car the mechanics would simply recommend me to change the entire unit.

How can i check my own and gather info

1. Is the coolant sensor working properly
2. Any pressure problems or water evaporating out
3. Determine any kind of unusual leaks or self diagnosis

 

Have you checked your oil? It has to be going somewhere, after you check your oil, if all is well put some cardboard under the car in the motor area to see if you can catch where it is going....

 

What gumby said. I'd be more worried about why the coolant is dropping than I am about filling it back up.

 

Take it to any garage with a cooling system pressure tester and have them test it. Laces a cooling system can leak. But a solvable issue

I wouldn't drive it until then. If it fails and drops the coolant you will warp and destroy the engine before you realize...

If low coolant sensor isn't working just replace header tank. Quick and easy. About $100 for the part. You can try and refloat / fix the sensor but prob not worth it

 

I have a 2010 XF with a 5.0, with similar issues. What were you able to determine was the problem?

 

I used radiator UV dye and a black light pen and found my leak - back of the engine - heater crossover manifold.