MFA and HU Intermittent power supply

Good evening, everyone.

I have used this forum many a time to solve numerous problems. However, I have only recently brought myself an 'All White' GTi Cabriolet and have a slight problem which doesnt seem to have been covered.

I have had a search or five but to no avail.

When I first picked up the car I noticed the MFA gauge was resetting itself, in that the time kept returning to 00:00. This wasnt really a problem for me until I changed my HU today and the problem seems to be linked with this HU too. Everything else seems to be functioning fine, all dash lights, speedo, rev counter etc. Just the MFA and HU So when the MFA gauge works, the HU does too and visa versa. This is a bit of a pain as when the HU loses its memory it reverts to factory settings and when the intermittent power comes back on it turns itself on and displays a 'Demo'. So I cant leave it like this as i'll always have a flat battery where it turns itself on and off.

My question is what connect's the two? Is it an earth or the permanent live? I did have some trouble getting the HU to work as it required a constant and ignition fed 12v. So I just cut the permanent from the golf loom and mated it with both the ignition and constant HU wires. (With thanks to this forum)

Any help would be greatly appreciated.
Kind regards,
Liam

I changed my HU today

Sorry if i am being think what is the HU ?

Sorry, I mean Head Unit or CD Player etc.

WightCab said

Sorry, I mean Head Unit or CD Player etc.

Got you , You should power the head unit direct via a fuzed link from the fuze board . Take a meter and search on the back of the fuze board you will find plenty of spare permanent live and some ignition live feeds . Your choice of power take off may have been a Red wire ? This is the permanent live feed to the clocks and keeps memory etc . Switched live for clocks is black wire .

Move the head wiring . Should sort you out ?  


Cheers …………

OK. I had read this in a post earlier today. However, as i had simply used the Red permanent live wire that was already in the stereo connections I did'nt think it would be a problem as thats what it was made for?

Also, the MFA gauge is intermittent with or without the stereo. It';s just when I install the Stereo the intermittent power also effects it.

I've had a little look and fiddle around the cab today. I tried to earth the stereo seperately today, but this had no effect on the situation. I then followed other advice from a previous thread and ran a permanent live from the fuse box, this sorted the steroe out and now I can only asume the MFA gauge has a bad live. Unless the MFA and stereo dont utilise the same earth?

But I have also noticed, while inspecting further, that the interior light and cigaret lighter do not function also. I am aware that all of these, including the stereo run through the same fuse on the box. Number 3 i believe. I have yet to replace the fuse although it looked OK. but i shall replace it in the morning. All I wanted to know was could these things not be working due to a bad live or a bad earth. As it was simply the live for the stereo?

Electrics, as you may have guessed, is a bit of a grey area for me. So any help would be greatly appreciated.

PS. I did notice that the earth 'cluster' above the fuse box was heavily corroded and i did spray it with some WD40 and I will disconnect tham all in the morning, clean them and reconnect. Just ot have an idea of what the issue could be would big a great starting point.

PS2. Now, when I turn on the stereo the dash lights come on, but quite faintly. Is this just because of the live feed I have chosen? lol

Many thanks,
Liam

For the MFA check the earth to the rocker cover in the engine bay. As for the others clean and report back.

Will do. Thanks