Mercedes Repair Questions? Ask a Mechanic for Answers ASAP
Thank you for your question and sorry for the delay in your reply.
My name is Steve and I am a fully qualified vehicle mechanic, you have not mentioned which model of Mercedes you have so I cannot confirm the exact quantity in the Adblue tank, but I would note that it will normally need topping up to above 15 litres of fluid before the warning will extinguish, I should note that the Adblue does not need changing but will only need topping up. Once this is done by turning the ignition on and off three times the warning should be reset.
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