Dash Wiring a mess, any ideas...

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FinalD
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Post Mon Dec 31, 2012 6:17 pm

Ok so I'm trying to work out why none of my dash lighting works and why the heater blower doesn't work either. I understand from someone else's thread that this could be due to an earthing problem. All of my earth points have their earths securely attached, but the wiring behind the heater controls/stereo is such a mess I expect I'm missing some earth there.

I've got loads of pics below showing the ever so nice mess, the car is a 1988 325i Cab, manual roof.

1) First things first, the glove box, do all these connections look fine? There are a couple of them that aren't connected (look like they shouldn't be anyway).
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2) Next up is the green plug from above. It doesn't actually plug into anything, I can't recall ever unplugging it from anywhere but I guess it is/was meant to be plugged into something.
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Next is the horrific mess of heater control and stereo wiring. Some lovely sod has used chocolate blocks to mash wires together. I don't really want to replace them until I know what is meant to go where, especially as they seem to have used different colours to BMW after the blocks. I'll break this down into different connections so it is easier to assist me (hopefully).
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3) Behind the heater control is this spare connector, I'm not sure if it should go onto anything, but nothing appears to fit it.
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4) On the same wrapped part of the loom as the top heater control bulb I have these nice wires. Any ideas where they should route? The brown spade connector one and the red and yellow bare one.
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5) On the clock wrapped wires I have some other oddly connected wires/spares.
The top chocolate block is a red and yellow thin wire that isn't connected to anything else.
The thick yellow and green one runs into what I'm guessing is the live for the stereo/ignition live.
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6) Here is the stereo area chocolate block which is a lovely mess.
The top chocolate block appears to be a red and white wire on one side and nothing on the other.
As for the rest of the wires, I honestly have no clue what they are for aside from somewhere in that lot is spear wire.
Also coming from the chocolate block that has a wire from the clock, there is a brown wire that leads to nothing currently.
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Any help is greatly appreciated as I don't know what complete moron butchered this poor car's wiring but whoever did it needs shooting. Once I know what is what I'll aim to get the correct grade wires and re-do all of the mess, neatly with proper joins etc. I'm even quite tempted to rewire the stereo stuff to a standard ISO connection then get an ISO > Sony connection to use the stereo that came with the car.
I do have the loom from the touring that I can butcher wires from but I'd rather not as someone may (for some odd reason) need/want that loom when I break the touring.
daimlerman
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Post Mon Dec 31, 2012 8:02 pm

willnz wrote:
When you are finished, find the bast*rd responsible, stuff his head in a microwave oven and hit the GO button.... :evil:
I believe that some-one did that to a cat recently,they are released sometime next year... :mad:
FinalD
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Post Mon Dec 31, 2012 8:41 pm

willnz wrote:Green plug is for the OBC immobiliser box. From the way the clock plug is cut into, you must either have an OBC or a non-working clock... 8O
No OBC and from what I can gather, the car wasn't specced with one originally although the spec sheet (online via the VIN) shows this:

S301A DIEBSTAHLWARNANLAGE MIT ZV Alarm system

The BMW alarm system was via the OBC was it not?

The clock does work (must be powered by magic), at least, I've seen that light up, nothing else does, aside from hazard, rear screen button and window buttons but those are built into the switches.

willnz wrote:The wiring is a proper mess, as you say!! I would use the touring wiring loom as an example to restore the loom back to original. Cut out ALL the non-OEM wiring behind the radio area. Get rid of all those nasty connector blocks.

All necessary wiring points for the radio/antenna are on the accessories plug behind the glove box. As you say, I would buy an suitable adaptor ISO-> whatever radio you use.

The large red/yellow and brown wires should go to the ciggy lighter. There should also be a thin brown and grey/red pair for the lighting for the ciggy socket. Check the touring's wiring..

When you are finished, find the bast*rd responsible, stuff his head in a microwave oven and hit the GO button.... :evil:
I think then that the best option here is going to be to remove the dash again so I can access all the wires properly to re-run them. What I'm tempted to do is splice the touring's wiring into the cab's, luckily that car is all OEM, but I feel that is a bad idea as I lose the other loom.
I'm not sure what grade wires I have reels of, I've seen RealOEM actually lists a reel of wire. I'd rather not lube myself up though so will get some from a local place if I don't have any spare.

The connector blocks will be going that is for sure, I'll do all the splicing with these as they are much neater and cleaner. I'm sure I have some shrink covers too so may solider the connections together instead and then heat shrink cover the joins. Either way, it'll be neat and clean, unlike right now. :P
Good fun day for me tomorrow then.
kam-325i
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Post Mon Dec 31, 2012 10:10 pm

willnz wrote: And dont get me going on chocolate block connectors... !!!!

Solder for the win!!

Better not mention Scotchlocks then !!!!!
Pete don't care about colour, He would shag a rainbow if he could find the end of it....
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Curr946
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Post Mon Dec 31, 2012 10:22 pm

I would get a dash loom from one of the breakers on here and start again.. that is a disaster waiting to happen
If your wife must learn to drive, don't stand in her way!
FinalD
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Post Mon Dec 31, 2012 11:12 pm

willnz wrote: And dont get me going on chocolate block connectors... !!!!

Solder for the win!!
Thought you'd say that...await a 'crap I burnt down the garage' thread, that or I melt the carpet (should be fine, done loads of soldering in the past). :P

I hate chocolate blocks, bulky and fall apart and just...urgh. Scotch are just as bad (if not worse) kam! :D
Curr946 wrote:I would get a dash loom from one of the breakers on here and start again.. that is a disaster waiting to happen
Bit pointless sourcing a new loom when I can just fix the one I have (properly), especially as I have the touring one to work from. Whilst it is a mess it isn't that bad a mess, it's only the stereo cabling which is properly bad, with the cig lighter and the clock/OBC wires being odd/bare.

Having had the dash out once already I know that without it there I have loads of room to work on the wiring and can tidy it up well and reroute any bits as I see fit.

I've not had any fuses blow so it shouldn't be too bad in that respect.