After installing my radio ( I'm confident that I connected the wires correctly) I turned on my car and noticed that the radio did not work. Now a few other things stopped working when the key is not in the ignition.

1. The Universal locking does not work unless the key is in the ignition
2. The headlight reminder tone (when leaving the car with the headlights on) does not go off
3. The dome lights work on the "on" position but not on the "door" position unless the keys are in the ignition.
4. The radio does not turn on whether or not the key is in.

I checked the fuses and none of them were popped out, I have no clue what to do? What could be wrong.

Clarification: Everything (besides the radio) works when the key is in the ignition on the "on" position.

 

Replace the radio fuse. Sometimes it breaks and you can't see it.
I had a problem like this, and it was just that fuse.

 

Did you check the fuses under the hood too? Power for the always on (yellow wire) circuit to the radio usually comes from a fuse in the box near the battery.

Saying which model you have would help.

 

Sorry to mention but it's 2001 Civic lx 4 door. I checked the fuses next to the battery, none of those were popped out either.