View Full Version : Putting in a new radio

21-06-2005, 05:17 PM
Hi everyone
I just got my red 42 about 2 weeks ago, and loving it! Thing is, the
old cassette player that came with it was a bit crappy, so I'd like to
put in the mp3 player from my old car. I connected it up, but it seems
there is one wire that is not connecting to anything. The wiring for
the sony seems to be reasonably standard - it worked fine in 2 other
cars, but it wont work in the smart now - something to do with
switched/permanent power?

On the sony's wiring, i can join the red wire to the yellow one, but
this does not work. If I just "plug and pray", it works, but only when
the ignition is on, and it loses all its settings every time i switch
off. Ive put up some pics of the wiring if it helps... (http://www.subvs.co.uk/doku.php?id=smart:radio) (http://www.subvs.co.uk/doku.php?id=smart:radio%29) Can anyone
tell me what im doing wrong?

21-06-2005, 08:06 PM
Hi Captainmish and welcome to the mad house!!

Grundig radios use a system of a switched supply for the main power, and a permanent feed for the memory etc, however, many companies invert these connections on their stereos, and as such although your unit is powered-up when you turn on the ignition, the power is TOTALLY lost when th ignition is turned off. The two wires need to be swapped. Its a simple job that only takes a couple of minutes, but I cant find the diagrams...sorry. Can't remember the colours, but if you do a search on the Smart sites you'll find 'em, or someon will be along later with help and words of wisdom.

21-06-2005, 11:12 PM
my blaupunktunit also has the same problem. It resets the clock settings each time the ignition is turned off for bout 3 or 4 hrs. If it is within an hour than the setting remains.

21-06-2005, 11:19 PM
apparently u have to swap the red and the yellow wires and then it'll
remember things, just found that out after a bit of searching. see
helpful and blonde ! ;):P

22-06-2005, 10:16 AM
I tried switching the red and yellow wires from the radio (there are
clips for doing this on mine) - but like that it didnt even switch on!
I will take some more photos of the things i have tried, and once I've
got it right I'll definately put up a little "howto" - it seems a
couple of people had/have this problem (at least i dont feel so alone!;))

I had a look on a couple of smart sites, but this one is BY FAR the
best, I posted on some orange nasty, and my post disappeared the next
day... I did manage to find a diagram in german, but ive forgotten
where it was now! Like I said, I will get all the stuff I find together
and put a PDF in the "how to" section when it works.

Thanks for the replies so far, and the welcome!

22-06-2005, 12:54 PM
I've been pulling wire again, I swapped the red and yellow again and
now it will not lose all the settings any more (I didnt time it, but
before the settings were gone *instantly*), This is a very good start,
but I'd really like to be able to turn on the radio when the car is off
(the old smart radio did this).

I put some more pics up here: http://www.subvs.co.uk/smart:radio so if
anyone could take a quick look to see where i'm going wrong, i would be
mucho grateful!

I did notice that there is a thin brown wire from the dash, that the
old radio was using, but the new one is not... could this be the
missing link?

Thanks again,

22-06-2005, 02:21 PM
Right to get the radio to stay on even without ignition put the red and yellow wire into the one yellow wire ( the connector will allow this ) see your pic:


Leave the spare "red" wire disconnected. Just remember to turn the radio off before you exit the car as it will drain your battery.

Hope this helps

22-06-2005, 02:26 PM
It then should look like this: ( without the wobly fingers :D )


22-06-2005, 03:22 PM
OK, I wont say anything about pulling wire with wobbly fingers :shock:
I connected them both into the big yellow double plug, and it also
keeps the radios memory, but still does not let me play with it while
the keys are out (while the ignition is off)!
Any other ideas?
Thanks again,

22-06-2005, 03:55 PM
Check the yellow wire with a multimeter, it should show 12v with the keys out the car as its a constant supply, the red is 12v switched.

Putting both cables (red and yellow) on the head unit to theyellow cable on the car will allow constant power to the unit.

( remember yellow cable on the car ) to ( red and yellow on headunit ) not the other way round.

chuffer dandridge
22-06-2005, 04:07 PM
Hi chuffer here, be careful when connecting wires, I wanted to do the same thing to my new sony xplod. I connected two wires together,cant remember which ones, result totally overode ignition switch!!! couldn't turn the engine off!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

22-06-2005, 04:08 PM
OK I will check when I get home, but the yellow wire is the radio's (those connections come from the radios wires, not the cars)


pink/blue red
fat brown black
thin brown *nothing*
blue yellow (and red too now)

The only wire from the car that the radio does not connect to is the
thin brown one, but i guess i just need to find out which wire gives
12V all the time and connect that?

Sorry for a dumb question (I have no idea about car electrics) but how
should i measure the wires, just from any metal bit as the ground and
then the positive on the coloured wires?

Thanks for being patient!

PS Chuffer, did you get it working with the car off in the end? If so,
could you possibly tell me which wires you connected where (mines also an xplod)?

22-06-2005, 04:46 PM
Captinmish, Are you going to Billing ? If you are i'll sort it for you, sorry its just so hard to imagine the stero wiring from being sat here.

I can't understand the cars wiring you have put down.

Can you please take a picture of the loom with both ends connected, just the loom with power etc, not the speaker one.

22-06-2005, 04:51 PM

Radio wiring:

Red = switched 12v (on with ignition)

Yellow = constant 12v (on all the time)

Blue = Illumination (comes on with lights)

Black = Ground

Now you need to test the Smart loom with a multimeter and pair these wires up as per above discription.

Make any sense at all ??

22-06-2005, 04:59 PM
Yep, thanks justrules - i have confiscated a multimeter from the
electrician at work and got a "auto-electric 101" course from him too,
so I will try and report back asap!

22-06-2005, 05:10 PM
lol, thats ok, set the mulitmeter to volts and for every test connect the black prong on to the ground terminal, then do the tests as above touching the red prong onto each terminal to give your reading.

Your + 12v constant is causing the problem i bet.

23-06-2005, 09:07 AM

Well its more-or-less working now, good enough for me anyway:
Just as I was about to give up and just accept that I would neve a
radio with the ignition off, I got it! During my messing around, I had
blown the fuse for constant power! I annexed the one for the cigarette
lighter and swapped them, so now i have the radio's constant AND
switched, both plugged in to the cars constant (with them plugged
correctly, constant to constant and switched to switched, it doesnt
work). It now doesnt care if the car is on or off, I just need to
remember to switch it right off when I get out :shock:

Thanks everyone for being patient with me!


23-06-2005, 10:47 AM
Glad you got it sorted dude.

23-06-2005, 09:24 PM
If Im not mistaken, you also have to remember to switch it ON to liven it up?

Reason for the original smart radio to be capable of being manually
switched on without IGN on is a software thingy within the radio. It is
(normally) set to follow the switched live, but as you push the button
it switches to the permanent live and stays alive for a preset time and
then dies so the cars battery isnt killed if you left it on by mistake.
I cant say Im up-to-date on other makes, but back in the ole days you
had the choice of letting the radio go alive and die with IGN on / off,
or you had to manually switch it on and off ( I wonder how many
batteries that solution has killed )

You simply couldnt have both at the same time

Should I have psted this a few days ago? Sorry, I wasnt here, then :dude:

24-06-2005, 11:19 AM
That sounds pretty much like whats happened to me... Its wierd though,
that when I connect constant to constand, and switched to switched, it
still doesnt work - aah well, I got my wish though - music without keys!
Hopefully this topic will be useful for someone else trying to figure it out!

24-06-2005, 11:30 AM
Nice one cpt. Maybe if you havea few pics and a rough guide to how you did it, i could put together a pdf how-to file for people in the same smart shaped boat as you :)

If you have just drop me a PM or email with everything i would need, and i'll try and put one together :)

24-06-2005, 01:58 PM
No prob, check the web page I made for this:
http://www.subvs.co.uk/smart:radio - now with interactive wire swapping
goodness, If you want any other stuff, I can send it to you. I will add
the "final" photo of the adaptor I used later today...

24-06-2005, 02:02 PM
OK, when its all present and correct i'll set to work on it. It'll be my 1st how-to aswell, LOL! :D

25-06-2005, 12:45 AM
Mmmmm, there is nothing like the first time /images/emoticons/singing.gif

29-06-2005, 05:15 PM
With all the connection swappings, i m a bit confused. Does that mean that if i want the radio to only turn on when i switch on the ignition and at the same time the radio keeps it's memories, ijust need to swap the red and yellow wires? ....which means the radio's yellow wire goes to the car's pink/blue wire and the radio's red wire to the car's blue wire? sorry...i m a bit blurred.

29-06-2005, 07:08 PM
Don't touch the cars wiring, I think Captinmish's car wasn't working 100% so he had to take the feed from some where else.

Try your head unit as it is, If it doesn't save your radio stations when you remove your keys then you swap the yellow and red over on the stereos loom.

If you want it to function all the time then you connect both to theyellow wire, again on the stereos loom.

Forget the blue wires etc as it should work as stated.

30-06-2005, 09:39 AM
I agree, it seems that my radio installing was a bit different from
normal, halfords said that no special wiring converter was needed, so
if the radio does not work simply from plugging it in, try swapping the
red and yellow wires, otherwise read the radio's manual and match up
the wires from that.