They did diagnostics on my car for what I (and they) thought was a faulty alternator. Turns out battery and alternator were fine and it was something else. They told me my car was as safe to drive and I could come back later if I wanted more specific diagnostics on air conditioning compressor. I was pleased because they were able to do this in a Saturda afternoon before closing, and I can now drive to work this week without worrying my car will die in the freeway! Thanks!