Car Stereos: Car deck off - After discharging 100% Car main battery, fuse tester, sony cdx

Question
My car battery discharged completely due to HeadLights ON (by mistake) After that when I recharged battery, everything started except (Car Deck-Sony-CDX-GTX60U) Checked fuses all are OK, Is there any internal (button cell) available in CAR Deck ?  Pl reply, Thanks in advance

Answer
Hi Chandra,

It's still almost certainly a fuse.  Check again.  There is usually 2 fuse panels.  One near your legs near the steering column, and one under the hood.  Test them fully with a fuse tester or multimeter.  Just looking isn't good enough.

Justin