Wiring loom replacement project

[mrscalex]

Who would have said when you started with the Scalextric - I am going to be tackling a small scale similar project to fix the loom of doom on my car as the central locking on the boot has stopped working and I also had issues with the boot light.. I have now a "donor" boot sub-harness that I am going to re-cable before putting on the car - planning to use silicone sheath electrical cable - not sure if there is a better option

I'm always having to replace wiring looms on older Scalextric cars. Bit of soldering required there but only 2 wires!

Here's an extreme but probably ultimate fix for the loom of doom.

Pull the whole boot leg of the main loom out of its cable runs. Pull back into the cabin. Remove the passenger seat and pull back the carpet. Then stagger the soldered in lengths down the rear bulk-head. This will give the closest to factory fix you can have by fully concealing the joins and allows you plenty of room to solder. I'd also order up lengths of cable in the right colour & size. From these guys who seem to do everything.

https://www.autosparks.co.uk/electr...pvc-cable-price-per-metre-9-0-30-5-75amp.html

Not sure what I'd do on the connector end as I'm suggesting replacing the cable all the way through. Maybe join onto a short length from the connector. Maybe re-make the crimped connection inside the connector.

Issue with using a donor loom is if it carries the same issues.

 

[Mario]

Whoa! maybe a bit too extreme for me, I was planning to do staggered soldered lengths but do it at behind the boot carpet around the area of the soft top pump or a bit further back, but still inside the boot compartment.

On the connector side I was planning to just solder the cable right at the terminal with a really short length of cable, as the cables don't bend there it should be fine.

I have been toying with the idea of making a "pigtail" just for the bend that breaks and use some sort of multiplug connector at both ends that I will then connect to the main harness on the boot and the boot lid harness in the boot lid, that will allow me to test continuity in the future for troubleshooting, but maybe a bit of an overkill... I reckon silicone cable is the way to go it should be really long lasting

Thanks for the link Robert will check it now

 

[mrscalex]

I just come out in a rash if I don't leave something looking like it left the factory. Pretty sad affliction

 

[Mario]

I know what you mean, if it was the M I would do it like you said but this needs to be functionality and long lasting, I might do the silicone pigtail minus the connectors so it looks factory,..let's see

 

[Vic-Z3]

Hi Rob.

Fantastic write up mate, luv your work and to have your son onboard is a bonus. Hope all goes according to plan.
Be great to see it back on the A Roads where it belongs.

 

[mrscalex]

Tonight we plugged in most of the connectors under the driver dash.

It was all relatively straight-forward. Except for this bl**dy connector. Or more specifically getting the old connector off to plug this new one in. It's the connector that sits through the bulkhead for the wiper motor. It's high up under the dash, difficult to access and is stuck solid. If anyone knows a way to budge it let me know! But I might need to tackle it from the engine bay side by accessing the wiper motor.

And here's all the old connectors from the original loom. They've done their job to point the way where to plug the new loom connectors in.

This is where the fuel pump relay (green) hides away. This whole bracket is part of the loom so has to be swapped. The old relays need to be moved across.

I reckon we're about 85% of the way there now. The outstanding areas are:

• Door multi-plugs on both sides
• Windscreen pillars on both sides
• Module rack under passenger dash
• Slam panel harness for lights
• Under the car/wheel arches
• Miscellaneous connectors around the fuse box including diagnostics port & alarm siren
• Audio harness.

I discovered that the audio system has a separate harness. Although it's bound onto the main harness in the factory making it look like one harness. I didn't distinguish and I cut through it when I should have saved it Fortunately I have a spare

 

[t-tony]

I cut through it when I should have saved it

So even someone with your expertise is still living and learning mate, I'm in awe of you Rob.

Tony.

 

[mrscalex]

So even someone with your expertise is still living and learning mate, I'm in awe of you Rob.

Tony.

No expertise round here I just read-up and try to be methodical & logical. Although in this case there was nothing to read up and and I had to go from scratch. I certainly got it wrong with the audio loom though.

 

[t-tony]

No expertise round here I just read-up and try to be methodical & logical. Although in this case there was nothing to read up and and I had to go from scratch. I certainly got it wrong with the audio loom though.

Maybe, but you did realise you got it wrong and that's the difference

Tony.

 

[Brian H]

It was all relatively straight-forward. Except for this bl**dy connector. Or more specifically getting the old connector off to plug this new one in. It's the connector that sits through the bulkhead for the wiper motor. It's high up under the dash, difficult to access and is stuck solid. If anyone knows a way to budge it let me know! But I might need to tackle it from the engine bay side by accessing the wiper motor.

There is a lock nut under the scuttle panel holding the connector in place.

 

[Brian H]

 

[mrscalex]

View attachment 90570 View attachment 90571

You sir are a legend. I would have been there for ever more otherwise.

 

[Brian H]

You sir are a legend. I would have been there for ever more otherwise.

Glad to help, there are advantages of having a scrap car lying about.

 

[mrscalex]

Today we did the legs up either side of the windscreen pillar. We nearly had to remove the dash just for that but we got there in the end pulling through with the old cable on the right and just loosening the dash on the left.

Repaired the binding on the donor audio loom - I accidentally cut through the existing one not knowing it was a separate loom. It’s definitely a 2 person job if you want to get the very long turns of the tape on like the factory did.

The connectors to the door looms. Which is where the main loom combines with the audio loom for the tweeters.

I finally removed the old wiper motor connector - what a pain that was.

And we ran the front lighting loom in.

We came agonisingly close to switching on. But it was getting dark and we weren’t quite there so we stopped.

I also seem to have lost the EWS module. So I’m going to have to program a spare tonight.

We’ve got a small number of final connections to make. Including under the car/arches. We’re just going to do the Speedo diff connector for now. Start the testing. Then do the brake pad wear sensors and wheel speed sensors when we have the brakes apart to check them over.

The loom is still only loosely fitted in most areas. We’ll ratchet up the cable ties when we’re happy it’s all working.

If we can get some daylight hour work in then we’re hoping to start testing one evening this week.

Ratcheting up the cable ties and replacing things like the windscreen top trim will probably have to wait until the weekend.

That just leaves replacing the interior probably in 2 weekends time.

So an MOT beckons sometime in Nov hopefully. Depending on if we find additional work that needs doing elsewhere on the car.

 

[Jjim]

Amazing work there. Well done to both of you

 

[Mario]

Amazing job buddy

 

[hard top]

Yep, as above from @Jjim and @Mario, just reading and looking at the photos scares the hell out of me, I would have no idea where to start on a job like that ....

 

[Clockwatcher]

@mrscalex,

What a cracking post. A great methodical approach, clear pictures and explanations. It's will be a good source of info for where connectors, wiring and electronic boxes are located around the car for other member's projects. Many thanks for taking the time to document it

All the best for when you turn the key.

 

[mrscalex]

Last night I completed the principal connections leaving just the audio, wheel sensors and a few odds and ends.

I was never going to try and start the car last night as James wasn't with me and we always do big switch ons together

But I did connect the battery up. The central locking did something and the boot courtesy light came on. But that was about it. What an enormous irony when it was the boot light that kicked off the original problem!

I did turn the key in the ignition to see if the dash lights came on but nothing. A check of the battery I was using suggested that was the cause as it was just under 12v which is pretty much flat.

However it was enough to get INPA connected and apart from 3x 'Aggregate or Open Circuit' errors I saw nothing that bothered me. These errors are hopefully circuits which are not yet connected.

 

[Mario]

Maybe I will be asking too much asking but... you should record a video of the firing it up moment for posterity after all this work I am sure I speak in the name of everyone here when I say ... we'd like to be there !!