Fitting Clarion headunit problems...

[harrishcris]

Hello,
I currently have a 1.4 TDI 04 reg which i want to replace the pointless tape player with a Clarion DXZ858RMP. I was told Clarion head units plug straight into VW's headunit wiring system, great! So i remove the current headunit, plug in the new one, all works fine but then i realise when i lock the door the flashing alarm light don't flash anymore. I can see other people on this forum have replaced there headunits but most seem to be pioneer which I’m assuming have different wiring. Anyone got any ideas? My local Autofile said (probably rubbish) that i needed to buy an aerial splitter so it splits the voltage from 12V to 6V otherwise it could damage my headunit? Anyone else heard of this? If anyone has any ideas on this then it would be much appreciated.
Cheers
Chris