Should I have to pay a diagnostic fee on a car I've only had for a week?

I bought a Toyota Auris from a main Toyota dealer a week ago. The car is a 16 plate, with only seven miles on the clock when I bought it. The car was a Toyota fleet car, so was unused for over a year. I've now done 450 miles in a week and the stop-start hasn't functioned once. My local dealer (a different company to who I bought the car from) wants a diagnostic fee of £48 to investigate the stop-start issue. Is this reasonable for a car under warranty? It would be paid back if a fault is found. Should I leave it a few more weeks to see if the stop-start eventually starts to work? Apart from that the car is great.
Reasonable for your local dealer to want £48 to check your car. Wouldn't be for the supplying dealer. Take it back to the supplying dealer. Keep all liability in one place. The stop-start won't work if there's insufficient charge in the battery, and that may be because the car was sitting for over a year. Probably needs a new battery and this type of battery is £200+ rather than the £60 average for a battery for a non stop-start car.
Answered by Honest John

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