Definitive Guide to Corrado Stereo Wiring. Mods pls sticky!

[smee 0]

There have been a few posts recently asking about the headunit wiring in the Corrado, so I reckon it's due a sticky! I've seen a few recommendations to look on the12volt.com, but I have, and it's wrong. I think they've just pasted the info from a mk1 or 2 golf. Also, if anyone's thinking, like I used to, that it's a case of RTFM, because it's in the owners manual... you've reckoned without the perversity of VW themselves since the later your manual, the less info it gives you about the stereo! For example, the following guide is from the manual for my old G60 (91), the manual for my VR (95) has the same page but without the wiring guide, and the 1996 manual I picked up recently has a page which basically says "stereo? go speak nicely to your VW dealership" :epicfail:

So here we go:

 

In the Rado, the wiring is on standard ISO connectors (the black and brown 8pin connectors behind the stereo unless some monkey has chopped them off) but not wired according to the ISO standard! VW's swap the switched and permanent live over in the connector for some reason.

 

The wiring code is as follows:

Red - Permanent live

Brown - Ground/negative

Brown/Red - Switched live (ignition)

Grey/Blue - Instrument panel lighting

Blue/White - Speed signal for automatic volume (only used on VW oem units AFAIK)

 

Don't connnect the blue/white one to anything or allow it to short to the body as it'll stop the spoiler working.

 

Hope this is of use to everyone!

 

CAVEAT:This info applies to both the corrado's I've pulled to bits, so I'm confident it's correct from 1991 onwards. I can't confirm if it applies to really early ones though. Can anyone with an 88-90 radio confirm?

 

2016 Edit: Glad to see this post is still here helping people! I've learnt since that the speed signal is also known as the GALA signal on later VW's and you'll need it if you retrofit either a VAG OEM satnav or a Becker H/U with navigation like the one I have in my mk4.

Edited August 24, 2016 by smee
Old times sake.

[captainredeye 0]

Having problems after removing the dash the stereo won't switch on also the spoiler is very very intermittent now. I have a Kenwood and the wiring has been butchered several times, I have not. . Changed any wires so is the same when it was working, the blue and white speed wire was connected to the stereo live ,earth to earth , red live connected to the radios ignition live, grey blue instruments connected correctly and the cars ignition live not connected to the stereo at all.

I don't understand how it could work in the first place but have tested the live and there is power to the stereo from the red live wire and the fuse is not blown so am I just unlucky and the radio happens to of died while removed from the car?

[VW_OwneR_85 2]

lol how come theres a speed signal to stereo? the faster you go the louder the volume gets? haha

[Benjevw 10]

lol how come theres a speed signal to stereo? the faster you go the louder the volume gets? haha

 

Yea to drown out engine and road noise I guess! Mk4 golfs have it too

[Kevin Bacon 5]

lol how come theres a speed signal to stereo? the faster you go the louder the volume gets? haha

 

Yep!

 

The freedom of the 90s.

 

Now you get the stereo getting quieter the faster you go with a "tut, tut" finger waving graphic on the stereo panel.

[Stonejag 10]

I've had an issue for the last few weeks where the radio turns off when I stop the car. More specifically:

 

1) I get in the car. The radio's off, and can't be turned on with its power button.

2) Insert key in ignition. Turn to accessories position. Radio can then be turned on.

3) Turn key to zero position. Radio stays on.

4) Remove key. Radio turns off, and loses all its settings.

 

Previously the radio could be turned on at any time and would stay on even after removing the key. This is what I would expect from having factory nearly-ISO wiring connected to an aftermarket headunit with the switched live pin constantly live and the permanently-live pin switching on and off with the ignition. Sometimes it still does this, loose connection behind the radio maybe? When I put the Audioscape pods and 4 Ohm speakers in I noticed the backlighting fades in and out with the bass like it's not getting enough power...

 

Dodgy ignition switch or dodgy wiring? I know it's a bit of a rats' nest behind the dash but I'm quite keen not to fiddle too much! I think the switched-live pin may have come loose, sound reasonable?

[_Meth 0]

Almost definately wiring. IIRC the VW's swap the wires around for the permanent and switchable lives for some reason, which confuses people.

 

Basically if its connected the right way round it will turn on and off with the ignition and if its not right you can turn it on and off whenever (like I can with mine). If it does it intermittantly then it probably means yours is wired up the same as mine but the permanent wiring is a bit iffy and means that when that cuts out it will have the switcheable live as its permanent power - which will cut out when you take the key out and it will loose its setting.

[Tigerfish 10]

IIRC, the switched and permanent live being arse about face on some cars is something to do with the ISO standard not being totally standard (in the beginning), and not all car/stereo manufacturers choosing the same standard. It isn't a VW specific thing.

 

 

Sent from my iPhone using Tapatalk

[smee 0]

Can I just say, holy thread resurrection!

[captainredeye 0]

Have done some investigating testing the wires with some odd results, there is power from the live and ignition live and the earth is connected, when testing the live with a bulb and the ignition on the fuel pump primes every time i test the stereo live.

When connected the stereo accepts and ejects cd's but it wont turn on and there is no illumination to the face of it. Need to find what and where the grey/blue connects too.

 

Replacing the instrument cluster wiring tomorrow as some of the wires are burnt out, will update if this changes anything.

[delfinis38 1]

great sticky thread..... these wires were doing my head in last night for 30mins until i read this thread.... simple fix this morning to swap them... cheers.

[captainredeye 0]

All done but still nothing from the instrument panel lighting grey/blue ,followed it all the way to the fuse board and no breaks in the wire so at a loss to what the problem is plus I have tried it with 2 desperate stereos.

[captainredeye 0]

My stereo now only works when the key is put into the ignition and turned one notch then it goes off and when the car is started will only come on if the key is wiggled while in the barrel, would swapping the ignition switch possibly resolve this.

[mad-dog 10]

So here we go:

 

In the Rado, the wiring is on standard ISO connectors (the black and brown 8pin connectors behind the stereo unless some monkey has chopped them off)

 

hahahahahaha some monkey hasnt just chopped them off in my car he has totally butchered them !!!!!! but thanks hopefully i can now sort the wiring out so if i get fed up of the lovely sound of my 1.8 16v i can listen to some music

 

:bonk:

[Stonejag 10]

I've had an issue for the last few weeks where the radio turns off when I stop the car. More specifically:

 

1) I get in the car. The radio's off, and can't be turned on with its power button.

2) Insert key in ignition. Turn to accessories position. Radio can then be turned on.

3) Turn key to zero position. Radio stays on.

4) Remove key. Radio turns off, and loses all its settings.

 

Previously the radio could be turned on at any time and would stay on even after removing the key. This is what I would expect from having factory nearly-ISO wiring connected to an aftermarket headunit with the switched live pin constantly live and the permanently-live pin switching on and off with the ignition. Sometimes it still does this, loose connection behind the radio maybe? When I put the Audioscape pods and 4 Ohm speakers in I noticed the backlighting fades in and out with the bass like it's not getting enough power...

 

Dodgy ignition switch or dodgy wiring? I know it's a bit of a rats' nest behind the dash but I'm quite keen not to fiddle too much! I think the switched-live pin may have come loose, sound reasonable?

 

This thread bubbling back up tot he top reminded me I fixed this! Turned out my fusebox had fallen out of its mountings during my steering column swap, which is one reason why I could never get the under-dash trim back on...

 

The fuse for the stereo is on the extreme-right of the lower row of fuses int he fusebox - so when it fell out of position it pressed against the bonet release and jiggled sideways just enough to break the contact. Since I never swapped the wires to the ISO standard, this cut the radio's switched live, and because it's in the permanent live position caused the radio to turn off. Simple really!

 

Stone

[VR6Pete 0]

Ahh good timing!

 

Ok how do I fix the issue of my Sony head unit loosing its settings etc... When I turn ignition off?

[VR6Pete 0]

So I take it that I just need to swap brown / red with red to get around this issue?

 

Cheers.

[seanl82 23]

Swap the red with the yellow iirc Pete. One is permanent live, one is ignition.

[Stonejag 10]

I've finally got around to taking the stereo out, and immediately wished I hadn't :lol:

 

There's an...'interesting' adapter from the car's twin-DIN to the small Alpine connector - highlights include a random fuse holder, ignition live attached to permanent live with a wire link (perhaps why my battery kept going flat?) and all the joints made by twisting the wires together and taping over them :cowboy:

 

Not sure how the load reduction relay would have coped with the two sides being linked together but I can't see it helping! Trip to Halfords tomorrow for a new adapter, I think...

 

Stone

[VAG-hag 0]

Hi all, could someone do me a favour please and let me know where the blue white goes in the block? I know it doesn't do anything but "tidy loom, tidy mind" and all that. Cheers dudes

[VAG-hag 0]

Anyone???

[g0ldf1ng3r 15]

Anyone???

 

is that the 'remote' wire? so as to switch an amp on when the head unit is turned on - thus no amp, no need

[VAG-hag 0]

i believe its no use to me but i want to put it back where it lives

[g0ldf1ng3r 15]

i believe its no use to me but i want to put it back where it lives

 

no danger m8

 

i can pull my soy out & have a look for you

 

when you say block - is it block which connects the factory loom to the block that goes to the stereo & the location of the blue/white wire in that block?

 

or the end which actually plugs into the back of the stereo

[VAG-hag 0]

Std loom there are 2 blocks that I have a converter for. One bloc is for speakers the other is for power etc. I believe the std place for the blue white is in the power etc block. Just a photo would really help.

 

Thanks very much