Head unit Sony cdx-5100 problem

Hello all

I have a 86 VW without any wiring harness installed i the car. Tried to hook up my sonycdx5100 player the other day but i couldnt get power to the unit.

I have three wires coming from the dash: Red (power) brown(earth) an a white wire with a blue stripe.

Connected the red wire and the brown to the unit,but no joy. I dont know what the third wire is for, but when i accidentally shorted it whith the chassis on the unit, the display illuminated..(still wouldnt turn on-just illumination).

I would really appreciate any and somtechnical clarifying on this. Ps: my old radio works just fine so the car wiring should be ok.

Thanks in advance

Hi

Thanks for the quick reply.  You are correct about the wiring. Can i test the player safely directly from the battery? Want to eliminate this as the culprit.

Can i just hook up the red wire to + and earth to the chassis

The player doesnt have a ISO connector at the back, just one sony? connector.

do you know what the yellow wire is for?

Also have a switch on the head unit whit 2 modes : A=cars with accessory switch on ignition B= cars without accessory switch. 

Sorry for the hopless newbie questions

cheers

yellow is battery 12 v ( constant power )   set your selector switch to  B mode and use only the red or yellow power wire ( you may even have to use them both together, depending on how the unit sums voltage )

or as i said, take acc power from your heater control circuit and set to mode A

Thanks for all help.

the first config either doesnt work (red+red) or blows the fuse (yellow+red together).

Guess I have to try to take acc from heater control circut and see what happens

thanks

Im really starting to doubt the contition of my head unit.  When I connected red+yellow (from the unit) to the red from the dash + black from unit to brown from dash the fuse blows and smoke comes from omes from the unit..(!). In other words: could this happen if the yellow wire (from unit) is connected to the red from the dash?

 I really dont wanna waste anymore time on finding wires etc. without being positive that my player i really works.

Is there a simple way of testing this without using the wires from the dash?

again thanks for the replies guys.