Little problem!

hey people, I connected my system to test it a week ago..naja there was everything, everything was connected correctly…from the cables..and connections.. so power cable to 12V from the end stage. chinch from radio to the end stage and remote cable from radio antenna connection to REM from the end stage and GND so mass to the body^^(does everything right?!?) well was happy..and the next day I wanted to try out a CD, then everything went for a few seconds and now goes nothing more..the end stage doesn’t even show power…s radio goes but still…. first I checked the security of the end stage and radio, and they still seem to be quite in order..d.h they are also .. well can I vll one help or vll tell if I have possibly done what wrong? many thanks to greeting markus