Hi - just puchased 1999 Polo for my daughters first car and we are trying to fit a new stereo. The problem is that there is no permanent 12v supply - the usual yellow / red wire arrangement has both wires connected to a switched 12v - I have checked with a meter and cannot find any permanent 12v supply. The previous owner has joined an iso plug to the wiring loom using bullet connectors and the stereo all works but obviously loses its memory - I am thinking I will have to find a perm 12v supply somewhere but I would have thought there should already be one on the loom to the stereo?? - any assistance would be really appreciated. Thank you very much indeed.

Hy! The yelow one is the memory, this wire you need always have 12 V and the red one is the ignition 12V. Check it!

Hy! The yelow one is the memory, this wire you need always have 12 V and the red one is the ignition 12V. Check it!

Hi - yes the wires are normally as you say BUT mine are different. I have the red and yellow wires from the iso connector connecting together with the red and brown/white wires from the loom - all four wires connected together which cannot be correct - checking with a meter shows that this is a switched 12v - I cannot see where the perm 12v is. The iso connector is connected to the car loom via bullet connectors and it appears that the person who fitted the previous stereo may have got something wrong here. I wonder if the red wire is actually the perm supply with a blown fuse or something, and the thinner brown/white cable might be the switched ignition wire.

Anyway, thank you again for your assistance - I will look in to this further tomorrow. I have fitted various stereos and this is the first time I have hit a problem.

Sorry I got one of the wire colours wrong...

I currently have from the loom THICK RED and THINNER RED/BROWN joined together and connected across to both the permanent and Ignition pins of the ISO. When I check across here I can see this is switched (ignition).

I think the RED wire should be permanent 12v and the thin red/brown wire should be from ignition???? I am guessing I need to split these and find out why there is no perm 12v on the red wire. I think I read that the radio was on the same fuse as the interior light and cig lighter - have to look in to this today.

Thanking you for any assistance and sorry for the waffle.

Sorry I got one of the wire colours wrong...

I currently have from the loom THICK RED and THINNER RED/BROWN joined together and connected across to both the permanent and Ignition pins of the ISO. When I check across here I can see this is switched (ignition).

I think the RED wire should be permanent 12v and the thin red/brown wire should be from ignition???? I am guessing I need to split these and find out why there is no perm 12v on the red wire. I think I read that the radio was on the same fuse as the interior light and cig lighter - have to look in to this today.

Thanking you for any assistance and sorry for the waffle.

SORTED - Exactly as described above - ignition and perm had been connected together and perm fuse blown. Separated wires - new fuse - all lovely!!