Replaced battery and now radio won't turn on

I replaced the battery in my 2000 Impala LS 3.8 and now the Radio (RDS, CD & AM/FM & Tape) won't turn on. It has a CD and Tape still in it and nothing happens when I push, or push and hold: Power, Disp, or any of the other buttons. It never showed any code on the lcd, never said locked, no dash errors. Only other weird thing is that sometimes the turn signals simply won't work. Usually, they do, but every once in a while, they simply won't click. Replaced battery maybe 3 weeks ago. Any ideas how to reset the radio? Maybe unplug the battery again?

check the fuse, if that's good, then i'm stumped. never seen one do that before unless fuse blew. then again it might be locked. as for the signals, the hazard switch is a known culprit, would be a good thing to check...wiggle the button a bit next time signals act up and see if they start to work.

Is it the big black square fuse in the driver's side panel (the accessories fuse) that needs to be replaced? Because it's black so I can't tell if it's blown without just replacing it, can I. Also, I tried just pulling on it and it seems pretty rigid in there. Am I going to do damage by yanking the thing out - or do I need to push some release thing? Thanks a lot for replying.

i have read some posts about a fuse being located on the back of the radio itself

I know when I changed the resistor card for the heater the new card from the dealer came with a new fuse also... On my acura if you disconnect the battery the radio will lock itself out but it will still show a code on the radio itself.... get luck let us know how you make out

it is marked RDO or somethig like that, and might be on the passenger side I/P fuse block

check for voltage at back of radio check wires connector etc. if radio does not light up there is no power to it. if display is lit then radio is locked.how long have you owned this car? you can use a test light to see if there is power to radio . also check all fuses with test light.