What laws are there to cover autmotive technicians in regards to fair compensation? Should techs be paid for all work performed, regardless of whether the customer is charged? The shop I work at does not charge diagnostic time to customers who decide not to repair their vehicle. I feel I should be compensated for this time, but I don't know if they have to pay me for all work performed.

I am not sure if an automotive "technician" is the same thing as an automotive "mechanic". The law looks at actual job duties and not job titles. If these are legally the same thing, then automotive mechanics who work for an Auto Dealer are normally subject to minimum wage but not overtime rules under federal law (FLSA). Interestingly, the exact same mechanic who is working for an employer who is not an Auto Dealer, a garage for example, is normally subject to both minimum wage and overtime. In both cases, all hours worked at during the workweek are examined.

http://laborlawtalk.com/showthread.php?p=959664&posted=1#post959664

http://www.dol.gov/esa/whd/regs/compliance/whdfs11.pdf