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ps2cho
05-06-2009, 08:54 PM
I got everything so far lookin good in my 1987 Mercedes 260E.

...but I can't seem to get any power from the ignition wire for some reason. The +12V constant reads 12v...but (ignition on obviously) the +12V switching wire reads nothing.

I have replaced the fuse in the fusebox and still nothing.

Would I be able to bridge it with the constant +12V? If so would it drain the battery if I made sure to turn off the radio before I left the car? (for a temporary solution until I can get an electrical diagram for somewhere to attach to)

fasfocus00
05-06-2009, 08:55 PM
did you turn the key and test the ignition source?

ps2cho
05-06-2009, 08:56 PM
did you turn the key and test the ignition source?

Yes I did.


I got everything so far lookin good in my 1987 Mercedes 260E.

...but I can't seem to get any power from the ignition wire for some reason. The +12V constant reads 12v...but (ignition on obviously) the +12V switching wire reads nothing.

I have replaced the fuse in the fusebox and still nothing.

Would I be able to bridge it with the constant +12V? If so would it drain the battery if I made sure to turn off the radio before I left the car? (for a temporary solution until I can get an electrical diagram for somewhere to attach to)

x1le
05-06-2009, 08:57 PM
Check your cigarette lighter and see if that's switched. Otherwise run it to an accessory in the ignition harness.

I personally wouldn't ever run it to a constant, but yes, it will work.

Beerdrnkr
05-06-2009, 08:58 PM
I have the same problem in my car Suzuki right now. I just sent a power wire to the battery and manually turned off the HU for a temporary solution. I'm thinking there's another fuse somewhere between the harness and fuse box.

ps2cho
05-06-2009, 08:59 PM
Check your cigarette lighter and see if that's switched. Otherwise run it to an accessory in the ignition harness.

I personally wouldn't ever run it to a constant, but yes, it will work.

Good idea about cigarette lighter. That will work!

I'm relatively new to electronics. I had bestbuy install my headunit in my other car because it was free...but I'm reasonably handy so I figured I'd give it a go myself this time.

That should do the trick. I'll report back if it doesn't.

Thanks!

SicAudio
05-06-2009, 09:30 PM
those old german cars usually have a weird relay setup IIRC so try something else that has switched power.

ps2cho
05-06-2009, 11:41 PM
those old german cars usually have a weird relay setup IIRC so try something else that has switched power.

Yep that worked so its powered up now.

I'm really struggling figuring out the wires for the speakers...this ***** :(
Spent the last hour searching M-B forums and can't find anything on what color wires that go into the fader are for the speakers.

oldschool4me
05-06-2009, 11:45 PM
they dont make a wire harness kit for that?

stocker08
05-07-2009, 01:01 AM
I had this problem with my car also. I just ran a new wire from an accessory fuse in the fuse box. Fairly easy. Haven't had any problems since.

ps2cho
05-07-2009, 02:37 AM
they dont make a wire harness kit for that?

They do, but it only covers the Ignition, constant, ground and power-ant.....all of which can be cut and done for free....sure its easier....but I'd rather save $35. I'll never take out this HU so its not like im making it hotswappable.

SicAudio
05-07-2009, 02:52 AM
and the way the electrical is setup on them is thru odd relay setups. constant power actually shuts off lol so much for constant power! have you seen the funky fuses the old european cars use? weird **** man. 22 yrs as a tech I never saw such a mess in my life as they are lolz.

ps2cho
05-07-2009, 02:56 AM
and the way the electrical is setup on them is thru odd relay setups. constant power actually shuts off lol so much for constant power! have you seen the funky fuses the old european cars use? weird **** man. 22 yrs as a tech I never saw such a mess in my life as they are lolz.

You mean these ? :D

http://www.joetlc.com/images/MBFUSEKIT.jpg

Beerdrnkr
05-07-2009, 06:12 PM
So what's the cause of this?

ps2cho
05-10-2009, 11:43 PM
No idea...

I got a question though -- My Pioneer headunit (DEH-2100I) won't save any of my settings....Is that normal? If I change the equalizer and turn off the unit -- then back on it won't save it.
Could it be possible I have the constant + ignition wires the wrong way around? Or would that not make sense?

SicAudio
05-11-2009, 12:03 AM
yes it has to have 12 volts 24/7 on the yellow wire.

ps2cho
05-12-2009, 12:55 PM
Thanks. That solved my issues :)

Any thoughts on what I should do to tackle this fader? Its a PIA....

There are no grounds routed to the fader itself. So I am not sure exactly what to do....I've found each cable for the RR and RL speakers...but no grounds.

SicAudio
05-12-2009, 01:56 PM
i believe that car IIRC uses a common chassis ground for the speakers but do not do that!!!! you most likely will have to rewire all of it.

bigaudiofanati2
05-12-2009, 01:59 PM
Check your cigarette lighter and see if that's switched. Otherwise run it to an accessory in the ignition harness.

I personally wouldn't ever run it to a constant, but yes, it will work.

X2

SicAudio
05-12-2009, 02:03 PM
red is switched, not yellow. he was talking about losing memory settings so the yellow wire is what was in question. it has to have constant power at all times.