very strange electrical issue

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dagzie
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Post Mon May 07, 2012 12:48 pm

well bought my e30 couple of days ago and first thing i noticed is the radio does not switch off when the key is removed, its an aftermarket stereo. so first thing i done was pull it out, to my surprise i found no wiring loom for a stereo. the power was coming from the heater fan switch and it was earthed near the glovebox and all speakers were individually wired, why hasnt my car got stereo loom? also to adf my interior lights dont work, but if i put click the drivers side light into the door pin position, a relay behind the glovebox clicks and it glows ever so slightly, (barely visible) do you think these problems could be joined? any help would be great, thanks.
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Brianmoooore
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Post Mon May 07, 2012 1:43 pm

Your radio is wired as it is because it was fitted by an idiot/bodger!
The radio loom for an E30 is very basic, and plugs into a four pin section of the accessories socket, behind the glovebox. The speaker wires should all be separate tightly twisted pairs, and not part of any other loom Bit worrying that the radio works with the ignition off, if it's connected to the fan switch, since there shouldn't be power here when the key is out.
" If i put click the drivers side light into the door pin position." ??? Don't understand what you are saying!
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dagzie
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Post Mon May 07, 2012 10:13 pm

little update on the interior light situation, when the switch is in the off position my tacho, mpg, and clock dont work so im guessing quite a lot of the wiring has been bodged ;(
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Brianmoooore
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Post Mon May 07, 2012 10:52 pm

Sounds like fuse 21 is blown, plus there is a back feed into this circuit somewhere, which has probably blown the fuse when the back feed is in the other direction.
Leave the light switch in the off position and pull out fuses, one at a time, until you find which one kills the tacho and clock.
I feel this may become a long thread!
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dagzie
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Post Tue May 08, 2012 1:45 pm

checked all the fuses yesterday and they all seem good including 21, will double check it today tho
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aimlessrock
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Post Wed May 09, 2012 11:03 am

Mate, sounds like your car was owned by a proper bodge artist at some point. I had some issues when I acquired my E 30 and after much testing (and frustration) I found a mobile auto sparky who went through the car and had to correct no end of bugs. Think he charged my 50 quid a day plus parts... It was with every penny as every thing now works correctly.
E30 320i Convertible (1989)
190 Mercedes (1988)

"there is nothing more expensive than a cheap E30"
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dagzie
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Post Wed May 09, 2012 12:37 pm

i think that is what ill end up doing to be honest because ive found a blue wire that runs from the electrical box behind the glovebox to somewhere behind the ignition cowling and i can tell its not ment to be there