Electric problem with dome light and factory remote entry
 

I may have screwed up the electric on my 2000 Protege ES, but I can't seem to figure out how. I have a few theories, but was hoping that someone here may be able to help.

I did two things yesterday... First I opened the rear passenger door and pulled the power to the automatic lock as the gear was broken and making a horrid noise. Second, I pulled the stock radio and replaced it with a used one my Brother-In-Law had saying around.

Ok, here's the problem: I don't seem to have proper electric working through the car. When I open the door the dome light does not turn on, if I have my headlights on and open the door I get no warning sound, the keyless entry system (factory installed OEM Mazda) does not work, and I get a check engine light. And to top it all off... The radio does not work either.

Does anyone have a general idea of what this could be? Does the motorized lock complete a circuit of sorts? Could there be a fuse that I just can find that's dead? I'm going to open the door back up and turn the lock back on, but I wanted to know of other options if that does not work.

Hope this is the right area to post in. Thanks!

Ben