Charged for an "exploration fee" twice. First tim...

Charged for an "exploration fee" twice. First time, they fixed a fan motor, and then there was a broken fuse. They charged a lot for that fuse and they shouldn't charge a second exploration fee if their first "exploration" for the fan motor didnt uncover the fuse problem. Several months passed between the first and second service, so they told me it might not have been thier fault. I think the 2nd $70 exploration was petty, considering the fact that I had already paid them about $400.