Have just bought this head unit and it has a dimmer lead - does anyone know to which part of my MY03 WRX it connects?

 

illumination / dimmer is usually orange, has it not got the iso connector on the back?

 

It may do but the iso block is on order and will hopefuly arrive on Monday. I posted this from the wiring diagram only.

 

It's on the ISO - don't worry about it

 

I still had to cut into the adaptor wires though - just must be an oddity with Alpines. Same applied to the 'always live' wire and the phone mute if I had one.

 

Yup, this is a feature on the Alpine headunits, I had to cut the orange wire on my adaptor loom and put a bullet on it so I could plug it into the separate wire from the back of the headunit.

The other thing I found is some of the new headunits don't come with the correct radio antenna adaptor, so has to be bought separately.