DEF problems

[Seb123]

Hi everybody,

I looked around the forum but couldn't find what I was looking for. I apologise if it was discussed before.

My partner just got an XF 2018 portfolio from her dad as he lost his licence. She was getting an error message with no engine restarts for a while. Because it was intermittent and miles left varying from 500 to 200 and back to 500 after reading a bit online I assumed that there might be a problem with a sensor. Also the car being just serviced a few months ago I assumed that it was topped up. Anyways surprise surprise the car the car doesn't start anymore. She is getting no engine restart when she presses the start button. Went to the shop and got two 5 liter bottles and filled it up. I was expecting it to start but I get the same error message. From what I read it takes up to 1 hour for the sensor to detect the DEF but I cannot start the car. Is there anyway I can reset or bypass that?

Sorry for the long post and thank you for your help!