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MFD/Stero Wiring

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Right, im going to try and explain this in the easiest way possible.

i now have the standard head unit plug and want to wire it into my GSI. now ive counted the number of wires in the car and the number of wires on the plug and i have about 4 spare!

the colors of the wires in the car are,

Brown/White - matched with plug
Brown/White - matched with plug
Brown/White - matched with plug
Brown/Purple - matched with plug
Blue/Red - matched with plug
Blue/Red
Grey/Green - matched with plug
Grey/Green
Black
Black/White - matched with plug

the ones above are not connected to anything and the ones below are wired into the stero.

Black - matched with plug
Red/white
Red - matched with plug
Red
Brown/Green - matched with plug
Green - matched with plug
Brown/Yellow - matched with plug
Brown/White - matched with plug
White - matched with plug
Brown - matched with plug
Brown/Blue - matched with plug
Yellow - matched with plug
Blue - matched with plug

so from the above i have the following wires left over

Blue/Red
Black
Red/white
Red

why would this be? can anyone send me a list of all of the wires that should be there and what they are for?!
 
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Hmm, by 'standard' plug, I presume you mean a 3 plug bit of loom from another Astra?

1 plug deals with just the speaker wires, 1 deals with the power side of the headunit and the 3rd is for the MFD functions.

Now I'm not sure if the 3rd plug is the same for MFD and TID use, so that could be a reason (unless you got the loom from an MFD car).

I'm pretty sure you don't need that 3rd plug for aftermarket stuff anyway (mine wasn't wired up), so best to try and ignore that for now I think :lol:

The 4 you have left over are perm 12v, switched 12v, speed signal and god knows. When you call these spare, are they spares on the new plug, or spares on the existing loom?
 
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the new plug came out of a GSi so is the same one that would have origionally been in my car.

by spare i mean if i connect the new plug up, these wires will be left over on the standard loom
 
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Ah, that's a bit gay then, although random loose wires certainly could explain why your MFD is up the ****ter.

I would suggest getting out a multimeter and seeing if they (well, the non-power related ones at least) correspond with any of the pins on the MFD plugs.
 
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err ok thanks lol, think im going to uncover something i really dont want to!

so the wires below that are left over should be.

Blue/Red - speed signal
Black - perm 12v
Red/white - unknown
Red - switched 12v
 
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If your car has/ had the factory fit alarm fitted as standard, you will have a wire on the loom that would have gone in to the original headunit. This wire would tell the alarm ecu if the stereo is removed and set the alarm off. Quite why anyone would want to nick the original headunit is beyond me.

Also on the loom, you will have a connection for an electric aerial, regardless if fitted to your model. There is also a wire for illumination control on the original stereo. With the exterior lights on (side or headlights), a power supply is fed to the headunit to reduce the brightness of the buttons etc. Unfortunately I can't remember the colours of the above wires, :sorry:

As already said, there are wires that go to the mfd/ tid. These are to display what the original stereo would be doing... for example radio station name, track number or direction the tape is playing.
 
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On Sport & GSi models I'm pretty sure the electric aerial feed is used to provide power to the bee stings internal amplifier.

It's on the ISO plug that deals with all the power stuff. Possibly blue.
 
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Im just looking at my Haynes so will try to figure out the extra wires but I know on mine after I took the original stereo out
and put in a new head unit I did have a plug which used to go into the original stereo left over but cant remember which colour
wires these are, I think these only went to the MFD to display the Radio Channel details anyway as only difference on mine since its been
unplugged is that the channel details dont now come up on the MFD
 
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Thanks for all ur help guys, once I get this done I'm gonna have to start searching to see where the real problem lies, anyone reckon that someones butchered the loom behind the dash? As the rest of it is still wrapped in factory foam. Need to work out why it's not coming on all the time rather than the when it likes phase it's on now lol. Have a feeling I'm opening a big can of worms with this lol
 
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right well this thing really doesnt like me, its gone from not working at all, to comming on when it wants, to now being on all the time!

so now it comes on everytime i turn the ignition on and all 3 lights will be lit up, radio, check, trip - the clock shows the time but still has a little F and the main screen will sit on break pad until i press the button on the stalk, then it will change to one of the trip ones, but these still show as F miles, F consumption etc.

also, when i turn the car off the MFD stays on, it does seem to turn itself off but after how long im not sure as i got bored of sitting waitng for it to turn off!! really wish it would either just die again or work as it should!!
 
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Yeah something ain't right for sure, then only real solution to this (I think) is going to be getting an MFD wiring diagram, and testing every pin on the 2 MFD plugs with a multimeter.
 
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what would that tell me? the valtage on each pin? im guessing the diag will tell me what they should be carrying? will it all be in the haynes book of lies?
 
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Well there would be voltage on some of them, but you're more looking for shorts and broken wires.

Haynes does have the info, but Mark T and Lefthooker have both written guides which might be easier to follow.
 
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oh and this randomly appeared the other day.



also since i took the battery out and put it back in its not come on, is there a power wire attached to the + side of the battery connector?
 

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