The Morbidmobile Blog

[Stephen Edwin]

Originally Posted by TomSaintJames

Hi all, would 16.5 amp 1mm cable suffice for the rear lights? This is what I've bought for the rewiring based on the fact that the fuse for the fog lights is 15 amp.

The 7 core flexible cabling that I've bought is of significantly smaller diameyer than what is on the car, it may be that the insulation is thinner but I haven't yet compared them side by side.

It might be desirable to have a higher capacity earth wire.

And if you want to do a Proper Job. I can find links to seriously flexible wire for you. Flexible wire is flexible.

*****

This eBay link sells various 7 core specifications.

https://www.ebay.co.uk/itm/7-Core-Ca...r=441563154603

There may be other and/or better available. I just happen to have that link watched.

*****

Do not bind the new loom tightly. That creates a stiff loom that is entirely unsuitable for a loom that must flex. Wire on the outside of a bent bend is stretched, mercilessly. EEK.

Or. Use a binding with some serious grip and serious give. An elastic bandage from the local pharmacy?

Maybe use corrugated flexible plastic "conduit".

*****



.

[TomSaintJames]

That's the very stuff I bought Stephen, in that there link. May make a start this evening so will have a think about how I'll fix/support it. One thing to start about thinner wires, they'll be much easier to route in the restricted are of the hinge.

[Laird Scooby]

Originally Posted by TomSaintJames

That's the very stuff I bought Stephen, in that there link. May make a start this evening so will have a think about how I'll fix/support it. One thing to start about thinner wires, they'll be much easier to route in the restricted are of the hinge.

Why not use the 7-core for the hinge area Tom? Would make life much easier!

Also, before pulling the old wiring out, after labelling each one with the functions (earth, ind L, ind R, s L, s R, tL, tR, RVS, fog), tie some string or similar onto it so you can use that to pull the new cable/wires in.

FYI :

Earth = earth wiring
ind L = left indicator
ind R = right indicator
s R = stop light right
s L = stop light left
t R = tail light right
t L = tail light right
fog = fog

Don't forget you have two tail lights each side, one is combined with the stop lights, hence the 21/5W bulbs. The tail light will be the dimmer of the two filaments. Also the number plate lights come from the left hand tail lamp feed, no separate wiring needed to be run in as you can pick up off the back of the tail lights on the cluster. Depending how they've wired things, you may find that to put the bulb failure light out, you may have to run the right hand number plate light from the right cluster tail lamps.

I don't know about your tailgate but on mine, there is a long grommet designed to fit in staggered holes on the body and tailgate - in other words the holes are a few inches apart to reduce the amount of bending the cable has to do in one place.

I still think you could save yourself a hell of a lot of grief, blood, sweat and tears if you sort out that earth crimp on the ofending cluster.

[Stephen Edwin]

The earth crimp sounds important on the cluster. But. It depends on earth to the car body? Both need sorting.

Or wire an earth direct from car body to the cluster.

*****

So David.

What are "W" crimps? What are their pros and cons? Will a serious e.g. CK ratchet crimp tool crimp them or do they need a "W" crimp tool?

[Stephen Edwin]

Originally Posted by TomSaintJames

One thing to start about thinner wires, they'll be much easier to route in the restricted are of the hinge.

The geography of my 240 tailgate is different. My plan re my tailgate wiring is of an ilk but also different to something David has just suggested.

I'm considering having a drilled and grommeted hole in the roof and a drilled and grommeted hole in the tailgate. Both within the area that is enclosed when the tailgate is closed. About say ten to twelve inches apart. Then, run wires through some flexible corrugated plastic conduit between those two holes. That means the wires inside the conduit are not flexed very much at all. Cushti.

That is how the washer tubing passes between car body and tailgate on my 1992 240. So it works.

[Laird Scooby]

Originally Posted by Stephen Edwin

The earth crimp sounds important on the cluster. But. It depends on earth to the car body? Both need sorting.

Or wire an earth direct from car body to the cluster.

*****

So David.

What are "W" crimps? What are their pros and cons? Will a serious e.g. CK ratchet crimp tool crimp them or do they need a "W" crimp tool?

It IS important! It's barely making a connection because it doesn't have a crimp on from the look of things and the insulation is trapped, causing a high resistance join.

Any standard ratchet crimp tool (CK or otherwise) will crimp a "W" crimp with the right dies in the jaws. HOwever for convenience, most people have two pairs of crimping pliers, one for the "standard" red, yellow and blue crimps and the other for "W" crimps.



That there be a "W" crimp, the nickname is derived from the crimped shape or the shape of the dies that crimp them.



As you can see, the die forms a "W" shape.

Originally Posted by Stephen Edwin

The geography of my 240 tailgate is different. My plan re my tailgate wiring is of an ilk but also different to something David has just suggested.

I'm considering having a drilled and grommeted hole in the roof and a drilled and grommeted hole in the tailgate. Both within the area that is enclosed when the tailgate is closed. About say ten to twelve inches apart. Then, run wires through some flexible corrugated plastic conduit between those two holes. That means the wires inside the conduit are not flexed very much at all. Cushti.

That is how the washer tubing passes between car body and tailgate on my 1992 240. So it works.

If you look back on pg 10 of this thread, you'll see whoever ran the wiring in originally attempted to emulate that form.

If you're planning similar, i'd say 10-12" apart is a bit too far, also using a rubber double-ended grommet with hose in between (for want aof a better description) would be better than flexible plastic conduit that goes brittle and breaks - it's not designed for that kind of flexiility. I have one such rubber animal i'd be willing to part with, found it this afternoon as part of a tailgate loom from an 800 fastback.

[Stephen Edwin]

David. I have been known to understate. Sounds important means it is important.

My point was and is, the earth crimp to the tailgate is only a half way stage. The earth circuit needs to reach the car body. Cushti.

*****

"W" crimps has gone perhaps orf topic. I'll email you. Either tonight or tomorrow I guess.

Your point re how to bridge a wiring gap between tailagte and car is interesting. Likewise I will email you.

[Laird Scooby]

Originally Posted by Stephen Edwin

My point was and is, the earth crimp to the tailgate is only a half way stage. The earth circuit needs to reach the car body..

My point is, the other cluster works as it should - therefore the fault lies within the tailgate! With that earth terminal being suspect and the lights displaying earth fault symptoms, that would be my first port of call and will probably fix the fault.

There are earths running back to the body already, the only faults are within that particular cluster that has a bad earth. Fix the earth problem, lights should then work as planned.

Of course, there may be a secondary fault causing other problems, without physically seeing the car with my own tools/instruments it would be hard to bottom out what exactly is going on with that diode array so just as hard to advise the next course of action.
Hopefully the secondary fault doesn't exist and it's all down to that bad earth i showed the photo of in my post earlier today.

[TomSaintJames]

Goodness what a lot of replies! Thanks for all the wisdom folks, however, unfortunately I sorted the PCB earth from the offending cluster last week or before (can't remember now!) by installing a new ring connector which, of course made no difference!

So dave, you don't recommend using the 7-core 16.5amp rated flex wire for the hinge area wiring? (I bought the same stuff that Stephen linked to on ebay). I was hoping to run the whole length of the new cable from just inside the roof to the clusters, as a smaller diameter duct/cable etc will be a lot easier to accomodate in the very restricted space around the hinge, the section of wire on the drivers side has actually been compressed by the hinge/bootlid because of the lack of space here.

As far as the causative fault, I am hoping that a new earth will fix it, i'll introduce a new one each side in the hope that the dash bulb light is mollified! If not then I am thinking maybe there is a problem with the cluster itself (PCB board faults) or a problem at the source of the feed wires in the main loom/dashboard (hope not).

Tonight I will plan the work, and hopefully have a good go at it this weekend.

[Stephen Edwin]

David. The other cluster working OK is significant indeed.

It remains important to ensure a good earth betwixt tailgate and body. Cushti.