306 cab dash teething problems

[NETSPACE]

Howdy guys, big noob here, I just picked up my 306 cab as a first car, mostly happy with it so far but there's one glaring issue besides the obligatory faulty convertible system. I tried installing a fairly old Sony stereo and was shocked to discover a drained battery the next time I started up the car. The system appears to always be on unless I disconnect the radio, and the adapter socket appears to be constantly outputting power aswell. I used a very cheap wiring harness adapter from the black and white of the 306 to the single 5 pin harness of my Sony stereo. Any advice on rejigging the wires would be greatly appreciated.

Cheers in advance.

[Mighty306]

The cigarette lighter socket can be set to output power regardless of ignition switch position. (It's changed by the location of the fuse in the fuse box. If you find the owners manual online you'll see info on this).

As for the radio, have you another you can try in there to check it isn't the radio itself? They're a common cause of parasitic draw. Either that or the wrong harness adapter is possibly being used.