back door wiring loom.

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bushcraft
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Whats the best cure for the common back door wiring loom piping between the door & body ?

Is it poss to obtain a new pipe , shrink wrap or something without removing all the wiring to retube it ?

Thanks

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Grecian
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Re: back door wiring loom.

Not sure but I'm about to undertake the operation. New pipe was less than a tenner from MB. Suspect one might have to remove some panels and disconnect a few wires though. How else you gonna get the pipe around them?

fixwin38
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Re: back door wiring loom.

Not an easy repair.....removing the door card only gets you to a multi pin plug... and the broken conduit clamped to the door frame..removing the rear quarter interior panel on the 460 means pulling all the plastic retainers out with a slotted tool like a dinner fork...some may break...they were GBP 1.70 each from MB... and quote the colour..the panel will come out of the channel at the top if you ease the bottom out first.. you will find the other end of the conduit clamped to a spring and a cluster of wires disappearing into the bodywork....each wire is colour coded so easy to identify and inline crimp after you have snipped them all at a point that will allow you to operate the crimping tool..pull all the wires through to the door end of the conduit and unclamp the broken conduit... replace with new section of conduit.. push all the wires through to a point where the conduit is not stressed and crimp up...any frayed wiires must be replaced not taped as the tape fouls the conduit and as a result conduit and wires bend when you shut the door rather that retracting through the hole with the help of the spring......you could cut the wires close to the multi plug but need to take out the panel to access the clamp anyway...the wires should not move inside the conduit ...it is the spring pulling conduit that stops the conduit from kinking when you shut the door.....there are two rubber ferrules that fit into the hole in the door frame and in the door to stop the sharp edges cutting the conduit.......two hours if you have everything to hand.....

Grecian
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Re: back door wiring loom.

Thanks. I think I'll probably end up replacing the lot as they've been properly bent and fraid through lack of conduit for some time now.

bushcraft
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Re: back door wiring loom.

I was thinking of using a braded plastic hose, of similar dia (water pipe type) , as the origonal ribbed piping dont look a good idea, to run smooth thru the hole back.

:shock:

Grecian
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Re: back door wiring loom.

I guess a bit of flexible hose would do the trick, similar to that which carries waste water from washing machines and dishwashers. I'd rather not comprimise for a tenner though. This link is very informative.

http://gwoa.co.uk/index.php?name=Forums&file=viewtopic&t=8017

bushcraft
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Re: back door wiring loom.

cheers bud :wink:

dentsmithy
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Re: back door wiring loom.

Some one has kindly filmed the process :wink:

http://www.youtube.com/watch?v=qn0OO9_Mcyc

Grecian
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Re: back door wiring loom.

I'm in the middle of replacing the tube...literally...and have come accross this odd bit of electrickery. Any ideas what it is and how better to do it? It's the rogue blue wire coming from the door pillar that I'm querying.

Tom

fixwin38
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Re: back door wiring loom.

Hi looks like somebody has tried to pick up a feed or earth.follow the wire to the other end.. no high level brake light or extra power socket??? check each service into the door wiper. heater. central locking. fog light.. then go back into the quarter panel and undo the spring and clamp on the old conduit and slice away...cut the wires as far away from the clamp as you can..insert the door side cable ends into the new conduit and using inline crimps join all the cables up again...any frayed cables will require renewing.the cables should be free to flex inside the conduit but the conduit is drawn by the spring as you open a close the door and moves the cables en mass. secure the conduit in the clamp inside of the door.....

stig
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Re: back door wiring loom.

When I did this job, I used 13 core trailer wire to renew the wires. It fits well into the MB conduit, provides some support for the conduit as well (won't squash) and also won't allow the wires to all break in one place as the original does, as the outer insulation of the 13 core spreads the flexing. 13 is too many, but I used 2 wires for each of the heated window wires (4 in total) as originally these are a larger gauge due to the current. I had 1 spare. You can leave plenty after the clamp in the door to join in, and in the quarter panel I had about 5cm out the end of the conduit which gave a nice amount of loop and freeness for the whole lot to slide when the door opens and closes.

Grecian
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Re: back door wiring loom.

Very helpful, cheers guys. Had to give up today in the end as the gromet and spring are also shot.

Most of the wires had fraid where the conduit had split so I cut them there. This of course means they'll need to be cut twice and I wasn't too keen on having two joins, so the 13 core trailer wire sounds like a good plan, that way the joins can both be outside of the conduit. I don't think there's enough room in the conduit for the wires and in-line cripms so was going to solder them together and use heat-shrink shrouding. Is that robust enough?

Where can one get 50cm of trailer wire do you think?

Grecian
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Re: back door wiring loom.

By the way. Think the blue wire might be for central locking which is presumably retro-fit?

fixwin38
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Re: back door wiring loom.

Hi I have 9 core trailer wire here ..I can post you 50cm.....try and trace the blue wire back to source... was that a power feed that it was connected to?? ....

stig
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Re: back door wiring loom.

Hello again. I soldered the wires at both ends of the trailer wire, no need to worry about bulk/flexing etc as all joins are outside the conduit, then protected all with heat shrink, and finally wrapped them together with self vulcanizing rubber tape, leaves a very neat joint. If you don't want to use solder, you could use either in-line joiners or you could use a connecting block which could be cable tied to the door/ inside quarter panel, for a neat result. PS, 9 core will be enough wires I think, but just make sure the ones carrying the load for the heated window are large enough, the originals are considerably bigger than the rest for central locking etc, that's why I used 2 for each.

Grecian
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Re: back door wiring loom.

Thanks again.

From memory I think there are 9 wires plus the rogue blue wire (but that can be reconnected at the body side of the conduit). Don't know if it was a power feed, it was twisted onto a black/yellow wire though. Does that denote anything in particular?

Could always use 9 core plus a large seperate wire for the heater - I've got some 2.5mm flexi in the shed I think.

Thanks very much for the offer Peter. I'll see what I can source from friendly garage first and let you know.

Cheers, Tom.

Grecian
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Re: back door wiring loom.

As an aside, is there ay scope fot taking a feed off of one of the power supplies to an additional 12v plug? It would be handy to have one in the boot. Could always put an in line fuse on it for added protection.

fixwin38
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Re: back door wiring loom.

Hi Tom Black/yellow appears to be a power supply to the rear window heater.....so the blue wire was live to somewhere.....do you have a handbook ..all the wire codings and circuits are in there.....

Grecian
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Re: back door wiring loom.

That's odd, I would have thought that the larger black wire was the power supply to the heater. There are 2 black and yellow's in the loom.

Grecian
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Re: back door wiring loom.

Just for information, there are 12 wires in total.

2no single core; black, both larger diameter.
1no 4 core; blue, white, green, brown.
1no 4 core; black, black/yellow*, green, brown.
1no 2 core; brown, black/yellow.

*The rogue blue wire connects to this one.

I'm going to try and get small lengths of single wires with the same colour sheathing then use a large heat-shrink sheath or possibly just some tape to keep them all together in the conduit.

This place sells it in short lengths http://www.autoelectricsupplies.co.uk/

Will let you know how I get on.

Grecian
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Re: back door wiring loom.

All done now.

The rogue blue wire went into the rear light cluster cavity and stopped. There was another loose wire coming out of the bottom of the cavity which wrapped around the bumper. Possibly an addition for towing or something. Anyway, I ditched them. Odd though as the wire it connected to was actually the switched live for the intermittent wiper??

In the end I soldered new lengths of wire to the existing ones, on the body side, where they had been cut and fed then all into the conduit. I then fed the conduit through the door pillar and into the door and clamped it all back in place [don't forget to put the grommet in first!]. I then trimmed the excess from the wires and used bullet connectors to join them back up. This made it much easier to work out what was what when I reconnected the battery.

The two large black ones are for the heated screen. [One live, one earth.]
The blue, white, green, brown is for the central locking.
The brown, black/yellow is the fog light. [Black/yellow is switched live].
The black, black/yellow, green, brown is for the wiper. [Black/yellow is switched live on intermittent, I think green must be switched live on constant as I'm pretty sure brown is earth but I didn't check that so may be wrong]

The black on the wiper loom is live from the ignition so I piggy-backed onto this and ran another wire back though the conduit to an auxillary 12v outlet (cigar lighter) with a 5amp in-line fuse. Not sure how much use it'll be but thought I might as well while I was in there.

I reckon this would only take 4 or 5 hours in a lit workshop and knowing what to do. However, it took me the best part of the weekend on a steep driveway, in the cold, starting from scratch. Last nights beer was well received.

fixwin38
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Re: back door wiring loom.

hI Tom job Well Done! and a guide to others with the same problem..463s have similar installation but wire colour codes are different... seasons greetings...

Grecian
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Re: back door wiring loom.

Thanks Peter, and to you. Like all these things, relatively straight forward when you know how. Better than writing cards and wrapping presents though!