Engine turn over fuel is good

Any one any tips to get secure off my car radio it's an o4 almera

Radio won't come on says secure

When the ac fan and radiator fan are on,the engine light comes on. When the fans are off, the engine light goes off. I have changed the air filter and alternator. I also did a diagnostic check but no… 

My Nissan almera don't flow from speed 1to2 but I move to 3,4 and5 it move fine behave like low gas