My car shows that it's got it low coolant. But I checked the Overflow and it's full. Where is the coolant sensor in could it be faulty. This is on the xj6. I did have a low coolant issue a while back but I get that repaired and it's not leaking anywhere. Any ideas? If anything I probably got a little bit too much coolant.

 

The Fluid Level Sensor clips into the bottom of the Coolant Reservoir (see item 3)




The sensor P/N is LNA5740AB.

Graham

 

If the sensor falls out of the reservoir, it will give a low coolant reading. I've had to glue mine in because the ridge on the sensor that clips into the tank has failed.

 

Also be aware that there is a small, donut shaped float inside the tank. If the tank was low or empty for a repair, that float can get stuck at the bottom position even after refilling which would give a low coolant light.

The float goes around the pin of the sensor, although it is enclosed by the tank. It is white and can be seen with a flashlight from the opening. A long screwdriver can free it up so it floats again. Hopefully, a cost-free fix either way.

 

The fluid level sensor rarely fails but can fail with time, particularly if the car might have experienced over-heating at some point. Good used ones are not much cheaper and would cost the same to ship so try get a new one.