Open Monday - Saturday. Saturday is for behind the wheel drive test only(Security guard told me). Check with them though.
Sat&Sunday Closed Open : Monday ~ Friday 8am to 5 pm
Google DMV Pasadena.
I don't know about Saturdays, but they are open week days. Also if you don't have an appointment your best bet is to go early in the morning (about 6 am) so you can get one of the 150 walk in numbers so you can do your visit the same day. When you get your number the employee at DMV will tell you at what time to came back so you can go inside an take care of your paperwork.
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