MEX BT3900U won't save settings!

[Charlie.Baldwin94]

Ok, so just yesterday I purchased an MEX BT3900U to replace my old stereo in my Citroen Saxo.

My problem is whenever I turn off the ignition and leave it for more than a minute, it restores all the settings to factory default, so I have to turn off the demo again and reset my radio stations. Also the stereo turns off when ever I open any of the doors.

Now I've read everywhere that I'm supposed to swap round the yellow and red wires. This sounded right as I had the same problem with a previous stereo and swapping those wires aroud solved it, however when I try it with this one I just get no power to the stereo at all and when I turn on the ignition nothing happens.

Any solutions?

I really like this product and don't want to have to return it so any help would be appreciated.

Thanks!

[Watashiwateshdes · Accepted solution]

Hi Charlie.Baldwin and welcome to the community.

Bit of a tricky one to answer but it seems to be that your wiring is slightly different to what the stereo is setup for which could possibly be down to the wiring in the car may have been altered. Either by the factory or by a previous owner if purchased second hand.

I would say go by trial and error but you do not want to risk shorting something out on the head unit or on the car itself, I have been there and it is not fun.

The headunit like most has a tiny power reserve which is why it retains info for short periods of time and then after that, reverts back to factory defaults or something causing the stereo to trip electronically when you open a door. The best recommendation I could give is have it checked by a car audio specialist. It could be the wiring or the head uint but really hard to say since each car and its wiring is a little different.

Not the clearest of answers to help fix the problem but maybe someone who can have a look over it all might be the best way.

Regards, Teshi