Hello, I have owned my 1998 Jaguar XJ8 VDP for just over a year and have been slowly tracking down and fixing the many issues these beautiful machines have. Since buying the car the low coolant light has been on. I recently replaced the level sensor however the light is still on. I know the sensor is receiving power because when I bridge the leads the light shuts off. Any ideas on how to fix the problem without needing to buy a new expansion tank?
Many thanks,
Noah E

 

Well, is the coolant low ?

 

The coolant is not low

 

That is puzzling if the light can go out when you close the circuit. As far as I am aware, there is only the sensor for coolant level, as you observed, in the expansion tank, Why not remove it (the tank) being VERY careful with the bleeder line nipple that runs a small hose to the thermostat housing ,I think, but the hose is the one small one from the top nipple pointing straight back) That nipple is prone to breakage. You may even want to remove the hose at its other end to avoid pulling it off, if you are trying to avoid buying a new tank, trust me on this one. It is an absolute point of failure.

Once you have the tank off you can possibly figure out where the sensor is failing. I think it's either a float or a magnetic sensor that is tripped by a metal float in an adjoining chamber or tube. Its probably stuck in the low position. Its certainly worth a try before replacement.

Actually I just notice you are posting the the X350/X358 forum. Not a major thing but the design of your expansion tank is different, as are myriad other things. Just FYI, you may want to re-post to the X308 forum. Good luck with the low coolant false alarm issue.

 

Noah - I am not sure how helpful this will be for an X308, but is worth a look:

https://www.jaguarforums.com/forum/x...arning-225484/