Recently aquired 2002 polo usuai boot not locking problems but more puzzling the original sound system was working until I  had to replace the battery.Fuse checks out ok but no SAFE display on the radio . Absolutely no life at all no way to tell if its on or off.I have code for radio ,could be dodgey earthing I suppose.HELP PLEASE

Welcome to the Forum.

 

I see that there is no answer to your question yet, maybe because anyone looking at this might think that all that they can do is guess at an answer/cure.

It seems a little odd that you only had this problem after disconnecting the battery - Under those conditions, it is normally loss of code that causes the problem - are you quite sure that the code that you have, is in fact the correct one?

 

Unfortunately, I too am unable to give you a definitive answer, but you could try the following:

Using a 'test light' (a 12 volt bulb with a pair of wires attached) rather than a voltmeter, check that the bulb lights to 'normal brightness' when you connect it to the live wire to the radio and to earth.

The reason for not using a voltmeter in this case, is that the bulb puts a little load on the circuit, so if it fails to light, or is only dim (compared to when you connect it to the battery) there is a poor connection, whereas a voltmeter could still show 12 volts.

If the bulb fails to light at all and you do have access to a voltmeter, now is the time to use it to see if there is voltage there at all - this could show the difference between a poor connection and a broken wire.

 

Regards