Dashboard lights come on when radio turned on

[Muttzcuttz]

Hey guys and girls

I've had a search but couldnt find anything that matched the issue I'm having, and forgive me, but Im a bit of a noob with wiring!

I replaced the head unit in my MINI with a SONY CDX-GT620U, used standard ISO converters to fit it, great!

However, when the radio is in standby (ignition on) all is normal, as soon as I press power on the head unit, the dashboard lights come on, the orange ones that illuminate the speedometer and the rev counter

I dont remember this happening with my old head unit

Other than the dash lights coming on, everything else is fine, it seems to have a constant 12V as it remembers the presets and the time when the ignition is turned off.

While I'm here, the cage doesn't seem particularly secure, I cant bend the tabs in it properly because of the 'ledge' where the mini head unit rested

Any ideas much appreciated, thanks!

[chris.lamb]

The ISO connector is wired incorrectly and the head unti is feeding 12V to the illumination wire for the instruments that usually feeds voltage to the radio for its backlight.

[Muttzcuttz]

Sorry for sounding dumb, I've checked and the only wires going into the back of the head unit are as follows (I've written down the label on the wires and the colours, i dont know what is needed, they seem to match to me. Can I just remove the illumination / dash light or will this stop the backlight on the unit working??

Sony Head Unit > ISO cable

1
2
3
4 +12v constant - yellow
5 power antenna - blue
6 amp turn on +12v - blue/white
7 +12v ignition switched - red
8 chassis ground 12v- - black


These match the following cables on the MINI head unit harness adapter

1
2
3
4 +12v constant - yellow
5 left rear +ve - blue
6 illumination / dash light - orange
7 ignition / switched 12v+ - red
8 chassis ground 12v- - black



I'm a bit confused. I don't want to wire something the wrong way in case things go bang

[chris.lamb]

so you have got amp turn on wired to illumination!
thus the radio tries to turn on the amp and instead turns on the cars backlight illumination!
disconect this wire

[SteveM3]

Chris is correct. It seems strange the Sony has so few connections, how does it know when you switch the lights on so it can dim the display. Also look for a white wire in your Mini's original wiring, this is for the amp of the aerial. You can connect the amp turn on blue/white to this. It seems a common problem with these ISO convertors that they miss out the aerial amp connection.

[Muttzcuttz]

Thanks for the help so far.
I ordered a new 16pin cable as I was getting nothing with the old one (no power at all, nothing).
Now I have the new one, only the main unit has power, the flip down fascia has no power and no display. The buttons do nothing, but the main unit is happy to accept and eject CDs

Any ideas? I should have just stayed with my original MINI unit