Splicing radio harness for Kenwood flip out DVD

I.ll try explain this as best I can
Have a 03 new shape leggy with the radio and a/c all as one unit. I want to install my kenwood 1 din screen into the car, have all the parts ordered so i set about adapting the harness to run the kenwood.

The prob is i cant just disconnect the harness from the back of the stock radio, coz then the a/c wont work, so i spliced in an iso connector block into the existing wiring. I have triple checked that all connections are correct, and soldered correctly,

The prob i am having is that when the 2 units are plugged in at the same time, my kenwood wont power up properly, it has power going to it, but keeps reseting. The stock unit works fine all the time, as soon as i plug out the harness from the stock unit, the kenwood works perfect. Does anyone know if the 2 units can be run spliced together. I have been careful not to have the 2 units switched on at the same time.

Is there any way to have the A/C work on one of these units without the stock radio?

Long winded and hope i explained it ok.
Auto electrician is next step....

Quick check would be to take a live from the battery (with inline fuse) and see is it due to the kenwood not being able to draw enough power from the existing cabling

Apart from that I'm stumped!

EDITED...

To add there is definitely a permanent live going to the kenwood rather than just an ignition live?? If not then your radio will keep resetting itself everytime you turn it off.

Did u try what I said in pm?k

Tryin it later today Dan, workin away today, cant wait to finish to give it a go

[quote author=dossie01 link=topic=21822.msg264251#msg264251 date=1267782190]
Tryin it later today Dan, workin away today, cant wait to finish to give it a go

[/quote]

if u want me to have a look later, let me know, im in citywest again all day, finishing up about 6