Ok I am trying to install sony cdx-L510x headunit into my 1985 mazda rx7gs. Now the problem I am having is I get power going to the unit because I hear it beap when I re-connect the negative on the battery and it will take in and spit out a cd. Now my problem is I can't get the display to come up at all. I can't figure out what the problem is. I have all the wires properly connected for the wiring harness. Any help? I bought the dash kit and wire harness from crutchfield.com so I am thinking I might have to call them but wanted to know if anyone knew anything here.

 

You probably have the constant power connected right (it allows the cd to eject with the main power off and it keeps memory) but you probably do not have the switched power connected right(thats what powers the headunit). There should be an inline fuse for that, couble check it.

 

Check to make sure you are getting +12 v on the acc. wire (red). If not it's probibly just a fuse.

 

Yup I ended up having to run a wire from my switchfuse under the dash in the fusebox to the red wire and it all works. Thanks guys . Now I just need to get the rear speakers connected somehow.

 

Glad it helped!