the thing that gets me about these diagnostic fees is the work involved is usually plugging a computer in or calling seat tech. then they complete work which has a 50/50 chance of actually fixing the issue despite the dealers saying they have the equipment and know-how to diagnose. Now, if i go to any other garage they dont charge the diagnostic fee, so why should i go to a dealer? well, here's a thought. you pay the diagnostic fee, and this fee includes a guarantee. That the work then done will only be charged if it fixes the issue. if the fault isnt fixed, no charge. and in fact, the diagnostic fee should be discounted against the repair cost, or provides a 10% discount up to the value of the fee. Personally, im staggered how incompetent and clueless dealers have been when ive used them and how its clearly all about what they can get out of you. oh and if you didnt know, the dealers routinely search places such as SCN for help to diagnose.