Headunit don't like cds when engine running!

[richie00boy]

Really, it has been on the three of four stereos I've had in my car, with no issues. It's how the display dims when you switch the headlights on.

 

[mikee55]

This is the end...

...of my loom.

 

[Jexx]

Really, it has been on the three of four stereos I've had in my car, with no issues. It's how the display dims when you switch the headlights on.

It's nice to have when done properly, but in the world of DIY head unit installation, it usually gets hooked up to the wrong wire(or doesn't function well with the existing illumination wire) and isn't necessary anyway.