I took my pioneer out and put the stock one back in. Thought I knew the code so I tried about three different times, failing every time. Finally I found the code but now it throws up error and wont accept my code. So question is what is wrong and how can I fix it. I guess I put it into some kind of safty mode.

 

disconnect ur battery for a minute then connect it back

 

I've already tried unplugging the head unit by its wiring harness, but it didn't work.