Jonothan

When I had my 2016 C220d SE serviced in June, the AdBlue tank was pretty full. It showed a range of around 15,000 miles. When I picked it up after that service, the tank was still showing full but the range had dropped to about 5,000 miles. It had had a software update so I thought no more about it. Some 5,000 miles later, the range had gone to 6,200 miles. The tank still showed full and it’s showing full a month later, it hasn’t budged at all, and the range hasn’t altered. The Mercedes dealership have just looked at it and say it’s showing no faults and working just fine.

Any ideas, anyone?