Hi all, proper noob question but i cant figure out how to get the stereo working and keeping the preset radio stations.....

I have a JVC after market stereo all wires and connectors are intact, so if i connect the iso's to the BMW block, the red to red, yellow to yellow the stereo will power for a second or two then turn off.... My previous car you had to swap red to yellow so i did this and nothing no power what so ever... the red wire going to the stereo has a smaller red wire coming from it if i join that to the yellow and leave the red to red the stereo works but does not keep presets, am i missing something here because i now have a yellow wire coming from the car going nowhere....

if i remember right in this dusty brain of mine red is + live and yellow is acc live u will need to join the red and yellow together from the iso block end for a perminent live for the memory

change the yellow and the red around,job done !!

or just join em all up together as its the permanent live not being connected properlt thats losing the presets !!

Just connect the yellow (thought it was purple!!) to the red dude, job done

That doesn't work as stated in OP.. i have swapped yellow to red and then there is no power to stereo... i will get some pics of the ways that i have tried.... its weird, im not a noob at fitting stereos but this has got me baffled...

As Dave says... Swap the red and yellow, these are common wiring issues across various H/U manufacturers ;)

Standard harness + adaptor ?

Many folk think the "DIN" plugs work all, but alas not.

Has the wiring been hacked?