- Joined
- Feb 18, 2016
- Points
- 231
- Model of Z
- Z3M Imola and Z4 (e89)
Fair do Rob I panic when I have to wire a stereo in 
No way would I tackle that job. Well done mate 
No way would I tackle that job. Well done mate 
Wiring loom replacement project
- Thread starter mrscalex
- Start date
Wish I had the patience, nerve and time to do such a job. Fail on all counts.
Assume north of £1K labour cost, assuming you can find a tradesman to do it properly. Not many Z3s will benefit from a new wiring loom I guess, great respect!
Assume north of £1K labour cost, assuming you can find a tradesman to do it properly. Not many Z3s will benefit from a new wiring loom I guess, great respect!
4 days * 8 hours * £80 p/h = £2,500. And £80 an hour might be considered conservative.Wish I had the patience, nerve and time to do such a job. Fail on all counts.
Assume north of £1K labour cost, assuming you can find a tradesman to do it properly. Not many Z3s will benefit from a new wiring loom I guess, great respect!
With the loom you could be approaching £4k.
Having pulled the loom through the bulkhead we were now keen to run it along its main routes and to start securing it where it made sense to. There's not a lot of room to move in the cabin and we were concerned about leaving it laying around where it may have got trodden on.
There are also some key initial locating/connection points that give a good indication of how to tension the loom and exactly how it should lay before clipping.
We started off with the positive distribution panel that tucks up under the passenger dash. This comes complete and pre-assembled on the loom.
Then we ran the driver side leg to the boot space. There's not a lot on that one. It ends in the smaller of the 2 positive connections and the long green fuse unit that sits near the battery. It also has the accelerometer sensors and seat plug. But the important thing is the loom has 2 built in locating studs, bound to the cabling, that can only go in one place (under the seat). That's the sort of thing we were looking to pick off to locate the loom. It also has the fuel pump and an earth on a branch so that was our first connection we re-made.
Then we ran the passenger side leg to the boot for the same reasons.
What I then wanted to do was to bite the bullet on 1 of the 2 areas I knew would be most difficult. The driver instrumentation and the DME (engine management partition) on the left rear as you look into the engine bay from the front. It had to be the DME first as that leg needs to pass back out into the engine bay and it was easier to do that before the instrumentation was connected.
There was a lot of stuff to get through a small hole!
Making a start.
And the final squeeze. I love this. We couldn't work out why the DSC (brake) module plug was heavily cling-filmed wrapped when we first unboxed the loom. Well the reason is it's the single most difficult item to pass through any hole as it goes last and through the tightest gap. 10 out of 10 to BMW for these little things that have helped.
A bit more tugging and routing and the leg was sitting nicely back where it belongs.
Now it all has to be plumbed back into this stripped out partition. The cabling/boards in the photo are part of the engine loom which is a separate assembly. The engine side of the engine loom has very few connections. The DME side has a lot more! And these seat inter-mixed in the partition with the main car loom leg.
First the 2 connectors had to go back on the DSC sensors. The 1st one was difficult hiding as it was under the brake pipes out of reach. The 2nd at the back was almost impossible and I ended up loosening the DSC assembly to create a little wriggle room. It took about 75 minutes to get the 2 connectors on, the vast majority of it the 2nd one.
The neighbour returned just as I had completed it. She asked how it was going and I said it was a good job she hadn't have arrived 5 mins earlier because the air would have been blue! I'm so lucky my Parents' neighbours are so understanding with all the Z3s and work that goes on!
Here's the start of the plumbing in of the main loom components.
Plugging everything back in took about an hour. And I was thankful to have another car sat next to this one for comparison. Photo of the completed installation next time.
This leg also has some wheel arch connections (eg the wheel speed sensor) but I'll worry about all these connectors probably as the last task.
There are also some key initial locating/connection points that give a good indication of how to tension the loom and exactly how it should lay before clipping.
We started off with the positive distribution panel that tucks up under the passenger dash. This comes complete and pre-assembled on the loom.
Then we ran the driver side leg to the boot space. There's not a lot on that one. It ends in the smaller of the 2 positive connections and the long green fuse unit that sits near the battery. It also has the accelerometer sensors and seat plug. But the important thing is the loom has 2 built in locating studs, bound to the cabling, that can only go in one place (under the seat). That's the sort of thing we were looking to pick off to locate the loom. It also has the fuel pump and an earth on a branch so that was our first connection we re-made.
Then we ran the passenger side leg to the boot for the same reasons.
What I then wanted to do was to bite the bullet on 1 of the 2 areas I knew would be most difficult. The driver instrumentation and the DME (engine management partition) on the left rear as you look into the engine bay from the front. It had to be the DME first as that leg needs to pass back out into the engine bay and it was easier to do that before the instrumentation was connected.
There was a lot of stuff to get through a small hole!
Making a start.
And the final squeeze. I love this. We couldn't work out why the DSC (brake) module plug was heavily cling-filmed wrapped when we first unboxed the loom. Well the reason is it's the single most difficult item to pass through any hole as it goes last and through the tightest gap. 10 out of 10 to BMW for these little things that have helped.
A bit more tugging and routing and the leg was sitting nicely back where it belongs.
Now it all has to be plumbed back into this stripped out partition. The cabling/boards in the photo are part of the engine loom which is a separate assembly. The engine side of the engine loom has very few connections. The DME side has a lot more! And these seat inter-mixed in the partition with the main car loom leg.
First the 2 connectors had to go back on the DSC sensors. The 1st one was difficult hiding as it was under the brake pipes out of reach. The 2nd at the back was almost impossible and I ended up loosening the DSC assembly to create a little wriggle room. It took about 75 minutes to get the 2 connectors on, the vast majority of it the 2nd one.
The neighbour returned just as I had completed it. She asked how it was going and I said it was a good job she hadn't have arrived 5 mins earlier because the air would have been blue! I'm so lucky my Parents' neighbours are so understanding with all the Z3s and work that goes on!
Here's the start of the plumbing in of the main loom components.
Plugging everything back in took about an hour. And I was thankful to have another car sat next to this one for comparison. Photo of the completed installation next time.
This leg also has some wheel arch connections (eg the wheel speed sensor) but I'll worry about all these connectors probably as the last task.
nice work Rob.. looks like you both done a cracking job there, all be it expensive.. but at least you know it will all be right when finished..
I had to do a repair on the loom in the boot part of my 2.8 as the wires had chaffed through and there was a few bare wires by the time i had pulled all the boot wiring through into the boot and heat shrunk and soldered the bad wires replacing som of the sections with different colour wires theres was about 16 wires in total, I had to repair.. alss there was some bad corrosion going to the main power wires that led to the electric roof pump.. they had rotted through and there was a lot of green copper dust.. where the wires had been chafing on those black loom support clip things... but now i know its all done and everything works as expected.. I always keep sections of loom that i have robbed in the past from old appliances like dishwashers and washing machines... came in handy for my repairs...
Al..
I had to do a repair on the loom in the boot part of my 2.8 as the wires had chaffed through and there was a few bare wires by the time i had pulled all the boot wiring through into the boot and heat shrunk and soldered the bad wires replacing som of the sections with different colour wires theres was about 16 wires in total, I had to repair.. alss there was some bad corrosion going to the main power wires that led to the electric roof pump.. they had rotted through and there was a lot of green copper dust.. where the wires had been chafing on those black loom support clip things... but now i know its all done and everything works as expected.. I always keep sections of loom that i have robbed in the past from old appliances like dishwashers and washing machines... came in handy for my repairs...
Al..
Top job mate, one big puzzle
Rob I am always very impressed by the way you apply yourself to these projects mate, and, to have your James helping and also obviously showing a keen interest in them can only bode well for Z3 enthusiasts for a long time. Well done both of you.
Tony.
Tony.
Some great Dad and Son time making the man to be. I’ve had my dad turn the air blue a few times and said not a word to your mom and don’t repeat them in front of me either
Loved doing stuff with my dad when he had taken the time, learnt some skills on how to do things properly and still learning off him at 76.
Loved doing stuff with my dad when he had taken the time, learnt some skills on how to do things properly and still learning off him at 76.
My dad was a plumber Mark, a job which never interested me at all, but, Shirl's dad, Reg, now he was a man I could , and did spend many hours with learning a lot of mechanical and engineering tricks of the trade when I was younger. A lot of what I learned from Reg I share on here.
Tony.
Tony.
Hoping to get it to the finish line, at least as far as completing the initial loom installation by the end of the weekend. Then we've got a 150 point testing plan (yes really) I put together to run through. Which might only be a couple of hours to do. But the fun comes if something doesn't work. All this as long as the weather is okay.
The car starting is not at the top of my list of concerns. That's a relatively simple circuit. And even individual dead circuits are not that much of a concern as it's only likely to be something not plugged in. It's if I get obscure errors in INPA. Loom based errors can be some of the most cryptic and difficult to get to the bottom of.
The interior reassembly is a good few hours work after the loom is completed.
And although it's a lovely maintained car by the previous owner, it's been off the road for 18 months now so will need a thorough check before it goes too far. Depending what I find there it could be back on the road before the end of the month or it could be a slow burn over several months given the time of year if I can't do the work in the garage - barely enough room to swing a cat in there.
The car starting is not at the top of my list of concerns. That's a relatively simple circuit. And even individual dead circuits are not that much of a concern as it's only likely to be something not plugged in. It's if I get obscure errors in INPA. Loom based errors can be some of the most cryptic and difficult to get to the bottom of.
The interior reassembly is a good few hours work after the loom is completed.
And although it's a lovely maintained car by the previous owner, it's been off the road for 18 months now so will need a thorough check before it goes too far. Depending what I find there it could be back on the road before the end of the month or it could be a slow burn over several months given the time of year if I can't do the work in the garage - barely enough room to swing a cat in there.
Well done Rob, rather you than me, would'nt know where to start
This is the sort of challenge that intrigues me and wouldn't mind giving it a go, however the issues that could follow would frighten the life out of me, I once reshelled an astra GTE, (jelly mould shape) had to remove the loom and fit it in the new shell, got lucky and it went well
We’re being very methodical. On the basis prevention of an issue is much easier than trying to resolve one.
It’s also why we’re using a new loom and not a secondhand one. A used one is easily damaged on removal if rough handled. And may have its own existing faults.
I’m not so stupid as to think we won’t have something not work first time. But fingers crossed it will be an easy fix.
Now painting a car. That frightens the life out of me But any issues we find will just get sworn at and fixed eventually
It’s also why we’re using a new loom and not a secondhand one. A used one is easily damaged on removal if rough handled. And may have its own existing faults.
I’m not so stupid as to think we won’t have something not work first time. But fingers crossed it will be an easy fix.
Now painting a car. That frightens the life out of me
But any issues we find will just get sworn at and fixed eventually
Well mate the weather forecast from Thursday onwards is looking very good so hopefully you will be able to make good progress.We’re being very methodical. On the basis prevention of an issue is much easier than trying to resolve one.
It’s also why we’re using a new loom and not a secondhand one. A used one is easily damaged on removal if rough handled. And may have its own existing faults.
I’m not so stupid as to think we won’t have something not work first time. But fingers crossed it will be an easy fix.
Now painting a car. That frightens the life out of me
Tony.
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 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