Battery wire not always on

[luzinit]

Guys, I'm about to go insane.

Just wired up a head unit to my dads car. It previously had a head unit, so it was simple case of matching all the colours, and soldering, or so I had thought.

Now, the deck won't hold memory, which is when the 12v battery isn't connected.

So I checked that with a test light, and it only comes on when the ignition is on, wtf?? so its basically same as the 12v ignition line.

I've checked different grounding points, all the same thing, it only comes on when the ignition is on, am I missing something?!?!?!

Any help is appreciated before I smash the head unit into pieces..

[zco]

smash your head unit into pieces and then use my advice lol
you got wrong wire cuz ! use your test light and find another wire.. i had same problem.. found the other wire and now its fine. hehe

[lilwilliam]

yeah as zico said use a light tester to confirm what wire is the positive, some wires nowdays for newer headunits use differnt colours to the old wires in a car=]

[Riviera]

http://www.installdr.com/

been here before??? basically has a full tutorial on how to install a head unit in a particular car

check if your dads car is on there, its very helpful tells you the modern day colours and the old school colours

[luzinit]

Thanks for the reply guys, but all the obvious things, I've already tried! That's what is spinning me out.

Trust me i'm using a test light! haha. theres 3 wires,

Red = presumably 12v ignition
Yellow = presumably 12v battery
Black = Ground

I tested both Red, and Yellow wires, both only come on when the ignition/acc is on. WTF!#@$#@%$#%$^%

[Jonald]

What kind of car is it, may help. I had a similar problem in the misses car. She had a second HU in there.

Can't remember exactly how i wired it. But if its the same car i may pull the HU out and have a look at how i did it

[luzinit]

Ok, found the prob. The previous deck for some reason did not use a constant 12v power. I don't know how it retained its memory for the stations etc though?? Old school deck from like 1991.. lol, prob used a battery cell or something haha. Anyways, just got the wire from the clock and all good now. Can't believe a deck install took me 3hrs#@$@$