My SRS came on last week and I am trying to decide whether this is a dealer or a mechanic issue. My mechanic charges me $70 for the diagnosis, the dealer $150. But the dealer said that usually this is due to a faulty buckle in the car and that if this is the case, the guarantee will cover even the diagnostics. Will it cover it at the mechanic too? Is there any reason for me not to go with my mechanic? Is there a way to diagnose this without spending so much money?