95 SLS starting/electrical/fuse problems!! please help!

I have a 95 SLS. Great car, just put a new engine in it a few weeks ago. Never had any problem starting the car, never failed to start. however, I had the dvd player and subs/amp installed. The fuses that they put in the amp were 15 and 30. The car was working fine. Yesterday, a friend of mine tried to replace the 15 fuse with the 30 fuse "guaranteed" that it would give more power to the system. However, when he tried to put it in, there were sparks and the other 30 fuse that was in there blew. Now the problem that I am having is that I can't start the car. When I turn the key none of the lights come on and the only time the engine will crank is when i close the door and step on the brake. Some electric things work such as the power doors, power seats, trunk but my windoes won't roll up/down and my gas tank will not open along with the car not willing to start. We disconnected the dvd player and the subs/amp, replaced the battery with a new one and still nothing. Any suggestions to what it could be would be greatly appreciated. Thank you.

I don't know what your friend did, but you will have to check all of the fuses in your car. See if any are blown.

:shakehead WHEN UR FUSE BLOW, IT BLOW 4 A REASON. SOMETHING GROUNDED. U NEED TO FIND THAT WIRE N CHASE IT BACK TO WHERE ITS GOING. CHECK ALL FUSES. BUT, SOMETHING U DON'T WANT TO HEAR, U MITE HAVE TO REPLACE THE COMPUTER. SORRY

just a note: increasing the size of a fuse DOES NOT increase power EVER, it only increases the size of the fuse. But this did not cause the fuse to blow either,if this did indeed happen as he replaced the fuse then you should check in that area for a wire the he may have moved and shorted.

OOPS, old thread