I have a 2018 Q8 bought with an extended warranty. The Adblue tank and control unit are faulty and will be replaced under warranty. The fault caused a leak and damaged electrical wiring. I have been told that I have to pay for the wiring as it's not covered under the warranty. Am I within my rights to argue that as the tank, which is covered by the warranty, caused the damage I should not have to pay for the wiring?