My head is still powered when ignition is off?

[Ritchie]

Hi guys,

Every other car I have had the stereo turns off when you turn the key into the off position. In the 406 I have just bought there is always power running to it when there was no key in the ignition. I could obviously turn it off with the head unit off button, but it would rather have it right for 2 reasons. The first being that it is a little frustrating and it would be nice if it went off when the key was turned. The second is that I have a blue tooth car phone kit which plugs inline with the standard ISO sockets and it is always on because it takes its signal to turn on from the ignition on power feed in the ISO plug. I have removed this to stop the battery draining until I sort it out.

What I have tried so far… I put a multi meter on the ignition on wire that goes into the ISO plug and it permanently has power running through it even with no key in the ignition. I figured this was the problem as the head unit was always thinking it should be on because this wire should (I am assuming) only have power running through it when the key ignition is on? I swapped that wire for a wire that I tapped into the cigarette lighter feed, as that only comes on with the ignition on.

The head unit now turns on and off when the key is turned on and off as normal, but it doesn’t remember what position the cd was in when it was turned off, what radio station it was tuned to when it was turned off or any of the radio’s settings like volume, balance, bass…

Does anybody know why this is happening? Any help would be greatly appreciated .

[Welly]

There's normally a switched live from the ignition and a permanent yellow? wire to hold memory etc. but it should go on/off with the key. Sounds like someone's butchered the loom/ISO wires somewhere for some reason.

See if somene else knows, there's a few on here that would know for sure.........

(welcome BTW)

[steve_earwig]

There will be two +ve feeds on your radio, one should be connected to the permenant you already had (for the memory) and the one connected to the switched +ve you just found. Sounds like they're both connected together. They might be red & yellow, like Welters says but you may have to experiment.

[Ritchie]

Thanks for the replies!

Somebody has definitely had a go at it at some point. I can see where wires have been messed about with.

Steve… when you say “the permanent that you already had”, do you mean the one I swapped for the feed from the cigarette lighter? If so, should that have been a permanent that I should reconnect up? I can’t remember the colour, I can have a look at tell you later if you like?

Welton… I might use the multi meter on the yellow wire that you mention and see what is going on there. If there is no power running through it then I guess that is where the problem is. I always thought that it was the red line that provided the permanent power to hold the memory.

[mjb]

Easier answer is check the fusebox. There's 3 pins on the sockets for the stereo and cigarette lighter fuses which let you put the fuse in one position for permanent on and another position for on with ignition

[steve_earwig]

[Welly]

[Ritchie]

Easier answer is check the fusebox. There's 3 pins on the sockets for the stereo and cigarette lighter fuses which let you put the fuse in one position for permanent on and another position for on with ignition

Now that has to be worth a look when I get home

[Ritchie]

Well that seemed to sort it!

I can't believe all the time I was prating about cutting wires all I had to do was change the fuse position

Thanks for your help!

[CountryPug]

Hey, just been reading through the thread as im having the same problem with the new headunit being constantly live, been into the fuse box however and i only have 1 position for the stereo fuses, the only 3 pin points are for the cigarette lighter???

help needed....

Quick update, after farting about with the fuses and wiring i've had some success. It turns out that when i pull the key out of the ignition the headunit is still powered, after about a minute the thing goes dead. What is more interesting though, is that when you come back to the car and open the drivers door, the headunit powers itself up again for another minute if you dont put the key in. i've installed headunits in a few different cars but this is probably the weirdest thing i've come across...its a D9 Hdi btw.

[mjb]

You need to modify the ISO connector as it sounds like you're taking power from the VAN bus, which carries a risk of damaging a lot of expensive electronic systems in the car. Use a standard ISO wiring diagram and remove all the connections from the power ISO plug apart from +12v permanent, +12v ignition and ground. If you've got the JBL amplified setup, you'll also need the power aerial line connected.

[CountryPug]

You need to modify the ISO connector as it sounds like you're taking power from the VAN bus, which carries a risk of damaging a lot of expensive electronic systems in the car. Use a standard ISO wiring diagram and remove all the connections from the power ISO plug apart from +12v permanent, +12v ignition and ground. If you've got the JBL amplified setup, you'll also need the power aerial line connected.

Thanks for the advice, I'll have to have a look before i do any damage. I havent got the JBL amplifier so thats one less wire to worry about