chocolate_o_brian

iTrader: (22)

Just purchased my Merc W124 off Moley_wrx's dad. Lovely car and all working electrics... BUT

He did warn me the previous owner had bodged the headunit wiring. So I've got the car without my little JVC jobby in and all these wires in the dash space floating about.

I have sourced this picture off the MBclub forum.



So is it a case of buying a male with female terminals ISO thingy and matching the colours up? I don't want to give the electrics a reason to go BOOM on me

Worth just having an electrically minded mate have a go for beer tokens?

TIA

500

If you can take a pic of the wiring and post it up, I'll give you a hand. The colours above are standard ISO colours and you won't have those in the standard MB loom, they will more than likely be on your modern stereo.

You may have a front/rear fader in the car as most mercs of that era have them, I'd bin it if it is wired up as it will alter the impedance at the headunit and cause problems

chocolate_o_brian

iTrader: (22)

It's rainign here at the min but as soon as it stops for a bit I'll get in the car and try get a pic of all the wires for you It's very messy under there with choc blocks with wires everywhere - definitely needs tidying up once and for all

chocolate_o_brian

iTrader: (22)

Pics as promised...







Now I've had a good delv and can count 13 wires not 17 like in the image I posted last night. What gives?

500

I'll do a bit of digging and get back to you with what goes where

500

Car--------stereo
Brown ------ Black ------ Thick brown on it's own
Black ------- Red ------ --- right of 4 way block, but check it is in it'sown terminal and not with the brown
Red -------- yellow ------ on it's own
white ------- Blue -------- far left of pic


Speakers, use the whites and grays if you have front speakers and the greens and purples if you only have rears. if you have a fader, you must take it out and extend the wires so you have 4 pairs of speaker wires to the stereo

the speaker wires on the car at the moment are the 2 pairs in the chock blocks at the bottom of the pic

vindaloo

ISTR you can buy an ISO plug with waire "tails". The wires are crimped and heatshrunk (or soldered and heatshrunk) onto the existing loom. Then the ISO connector plugs into the back of your HU.

This, or similar for cheaper... http://www.maplin.co.uk/universal-iso-plug-set-99497


Cheaper : http://cpc.farnell.com/jsp/displayPr...-2072-00001000

J.

chocolate_o_brian

iTrader: (22)

I can see the brown to black. For the black to red, did you mean the left of the block? If so, yes it's its own block away from the red one. Can see the red to yellow one. White to blue, is that the grey one you mean (bad photo looks whitish).

I don't follow your last paragraph. There are 4 speakers in the car, 2 in the front dash near the A pillar and 2 in the rear parcel shelf. I'm not clued up with faders etc, sorry if this sound "fick"

Cheers

Also looking on this link, the wires in the black power connection don't all colour match the generic image I posted earlier

http://www.maplin.co.uk/universal-iso-plug-set-99497

The black matches, the red matches, the sky blue matches, but then there is orange, red/yellow stripe and white; to match with brown, dark blue and blue/balc stripe

500

Do you have 1 of these in the car?




Black one, sorry about the 4 way bit, follow it back to where it goes into the other block and make sure that it isn't connected to the brown behind the tape

Grey one yes, it turns to white a bit further down

The only colours that you need on the black power ISO are:

Black which is Earth
Yellow which is live regardless of key position
Red which is live when ignition is on
Blue which is Areial remote, give it power, aerial up, take power away, aerial goes down

Forget about the Orange/Brown (depending on diagram) this dims the display slightly when the lights are on, most stereo's don't have this feature
The other 2 wires are not normally on ISO connectors anyway

chocolate_o_brian

iTrader: (22)

I don't think it has, because looking at a downloaded PDF manual, any fader switch is supposed to be on the console behind the gear stick. There should be 4 electric wondow switches with a child safety switch and then the fader ****. On mine, it doesn't have that so looks like a job saved

I should with the above, be able to sort this myself now, fingers crossed.

500

If you get stuck, send me a PM with your number and I'll give you a bell.

Do you have a multimeter? would be handy if you have access to one

if there are only 4 speaker wires, you need 8 (2 per speaker) as the impedance will be wrong and you could blow the amp IC in the stereo, if there is no fader then it may be easiest to get some speaker wire and re-wire the speakers

chocolate_o_brian

iTrader: (22)

I think (but I'll check when I can) that there are 2 wires for each speaker as the ones in the 2 blocks of four seem to go into a main wiring loom or something. Basically it doesn't look bodged. Moleys dad said it worked fine when he had his stereo in so I'm assuming I just need to wire mine in as per your destructions

I've never used a multi meter (fick moment). How would it tell me about the speakers or other wires? You can tell I'm a mechy fitter by trade, not a sparky

chocolate_o_brian

iTrader: (22)

Just thought actually, if I could get access to the speakers and check there is 2 wires off each...

Oh no, another question, if there are 2 wires per speaker (positive and negative?) how do I fathom which does where ?

NAF

Put a small battery (1.5v) across the terminals and watch the cone . If cone pushes out then battery is positive to positive and negative to negative so in other words what ever wire is on the batterys + side is the + wire from the stereo ...

Hope that makes sense

NAF

Have a read here COB

Explains it better than I could lol

http://www.carstereo.com/help/Articles.cfm?id=67

chocolate_o_brian

iTrader: (22)

Thanks NAF. Will scour that tomorrow.

500

Looking at the wiring again, then that does make sense that the speaker cables are the 2 blocks of 4, the black/red black green will be the rear.


so..

black with green stripe = right rear speaker (+) Purple on ISO
black = right rear speaker (-) Purple/Black on ISO


black with red stripe = left rear speaker (+) Green on ISO
black = left rear speaker (-) Green/Black on ISO

Brown/green White on ISO
Brown -------White/Black on ISO

Brown/Red Grey on ISO
Black -----Grey/Black on ISO

---------------------------------

Red ---Yellow on ISO
Brown --Black on ISO
Black --Red on ISO
Grey ---Blue on ISO


We got there in the end!

chocolate_o_brian

iTrader: (22)

Thank you

Not had chance to do it yet for the obvious reasons But will get an ISO and try whilst I'm on maternity leave mate.

chocolate_o_brian

iTrader: (22)

Aaaand, sorted !

Went round to Alcazar's today as he had some soler, an iron and heat shrink. Followed how you wrote it up and it works beautifully. Can fade to front, back or side to side (with the headunit, not a fader button) and the standard speakers aren't too bad.

I can bellow out "ze German trance" now

Cheers Jezza P and also 500!!

alcazar

iTrader: (2)

My thumb hurts where you burnt it with the soldering iron

Oh.........wait............that would have been me

Maz

iTrader: (34)

Nice one. Glad you got it all sorted in the end.