Cheers. I've made a little more progress. From the RDCM the wiring runs up above the subframe that holds the rear diff and suspension tie arms. Above that subframe it joins another harness that runs across the car. That's as far as I've been able to trace. By passing the connector above the subframe and back I can see a little more of the length.

There were signs of damage where the loom runs over that subframe. I think that was mentioned in other threads, but I didn't think it would be so well hidden/inaccessible. Interestingly the loom is wrapped in sticky tape, not proper sleeving, suggesting it's been worked on before. At the point of damage the insulation of the power conductor was cut, and the copper strands basically corroded to nothing.

So I think I know where I need to make the repair, the problem is that I can only just see where I need to work, and with all the stuff in the way I can only really reach with fingertips. Current plan is to see if I can cut back from the damage, solder a new wire onto the old, then rejoin that nearer the connector.

If anyone knows how to route from the RDCM into the rear fuse box that would make life a whole lot easier as I could basically bypass the bad cable altogether. ----------
Tony S

Glad to hear that it looks as if you have found your problem.
If you have to replace the wire, and it needs to be passed through a hole/grommet, be carefull to thread it through slowly as it is easy to create friction burns (& damage to insulation) on adjacent wiring. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 79k+ miles) (MY2015)
Metro in its 11th Year of (Extended) LR Warranty / Full LR Service History
(Expensive, but Trouble/Worry free - hopefully?)

Quote:

If you have to replace the wire ..

If only! There's no possibility of accessing that wiring harness without serious dismantling, nor can I find how it routes to the fuse box.

It's really crappy that Land Rover installs the cable in a location where it's going to chafe, and protects it only with a wrap of PVC tape. Yet another indication that long term maintainability isn't a Land Rover priority nowadays - if it's good enough to last out the warranty period then that'll do them.

So this morning I decided to crack with what was possible. By routing the wire back over the subframe and putting a bit of tension, about an inch is visible on the "good" side of the damage. I was able to tin that after stripping back and cutting off the corroded part,

Click image to enlarge

Solder on new wire ..

Click image to enlarge

Click image to enlarge

Rejoin ..

Click image to enlarge

Back in place after wrapping with harness tape and adding some spiral wrap for good measure ..

Click image to enlarge

And the proof of the pudding ..

Click image to enlarge

 ----------
Tony S

Well done, now all you have to do is sort out that corrosion! (Now Sold). 2008 Freelander 2 (Nazca Sand) SE TD4 Auto. Statutory write off & on WOVR for hail damage but still road legal.
171037Km as of 09/05/22
Superchips Bluefin Flash
Nanocom Evo II (also sold)

Tony
Fantastic job.
I think the lessons we have learnt, by watching your progress, will be needed by most of us in the years to come as our cars get older. I note the elusive CANbus white-white/blue twisted pair in your pictures.

Land Rover are not unique in having hard to maintain products. I think that there is always a fight between the ease (and cost) of building/producing a product, and the ease (and cost) of the ongoing repair and maintenance.
Over the last 60 years I have seen that car wiring has become better designed, but also much more complicated. I hope that now they are designing the chassis to accept electrification that at last wiring loom routes will be designed into the original architecture.

My initial training and career was in avionics, where utmost care is taken in the routing of cables, so I was rather disappointed when I moved by the wiring problems that occurred when I moved into commercial telecoms and computing.

Thanks for your pictures and feedback.
Ian FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 79k+ miles) (MY2015)
Metro in its 11th Year of (Extended) LR Warranty / Full LR Service History
(Expensive, but Trouble/Worry free - hopefully?)

Hi.
I'm probably 5yrs behind on this thread.
Remember these are fords not landrover.
No care is taken at any point in the build of these.

Anyway. I've been experiencing the same issues.
Replaced ECU and pump.
I know my haldex better than my wife.
Just had a message from bell saying wiring loom.
So found this thread, now to go routing to find the rascal. I'd already replaced the 8 pin connector just in case, and was working on poss a bad earth.
But chaffing on the wires works.
Anyone fancy popping down to the design department and opening a can of whoop ass.