BMW compact cup wiring help. (E36 318TI)

[Wazbeyondthewall]

Hey, I’m pretty new to doing up cars altogether however most of the project is done except for wiring, and final finishes so the car doesn’t look like a mess. Wondering how I’d go about striping the cables, and what ones I should strip.

I found a bmw manual of all the cables but so far not looked over it too much.

Picture of the wiring: https://imgur.com/gallery/bLZpzn9

[GreenV8S]

Wazbeyondthewall said:

Wondering how I’d go about striping the cables, and what ones I should strip.

Not sure what you mean by that. Are you thinking about eliminating part of the loom, or just protecting/securing/tidying the wires in the existing loom?

[Penelope Stopit]

Start off by putting a list together of everything electrical that you need to have working

Are you using a BMW ECU and instrument cluster?

[Wazbeyondthewall]

I'll be installing an ECU and the car has an instrument cluster already.

I'm pretty much trying to take out wiring i don't need. Radio, ABS etc

[Penelope Stopit]

With this being new to you, you will need to find out what can and can't be removed
For instance,the cluster and ECU are programmed to the car
If you are getting rid of the standard BMW ECU and cluster you should make a wiring harness from scratch, most of the standard loom is not needed
I am guessing that you only need lights, wipers and fuel pump plus the engine electrics and cluster

Do you know how complicated this job is?

What year is the E36?

[GreenV8S]

Wazbeyondthewall said:

I'm pretty much trying to take out wiring i don't need. Radio, ABS etc

It looks as if the interior has been stripped out. What electrics do you want to end up with? For example do you just want a 3rd party ECU and brake lights, or is this destined to go back on the road with aircon and electric windows and so on? This will determine whether it's sensible to take the whole loom out and replace with a minimal loom you will create, or you are just thinking about removing a few redundant wires.

[Wazbeyondthewall]

Penelope Stopit said:

I am guessing that you only need lights, wipers and fuel pump plus the engine electrics and cluster

Do you know how complicated this job is?

What year is the E36?

Yeah pretty much everything you've listed I'm keeping.

To an extent, out of everything in the car it's something I have no experience with at all. Toyed with bringing in someone to do it for me, however would at least like to have a base understanding of what's happening.

It's 1999.

[Wazbeyondthewall]

GreenV8S said:

It looks as if the interior has been stripped out. What electrics do you want to end up with? For example do you just want a 3rd party ECU and brake lights, or is this destined to go back on the road with aircon and electric windows and so on? This will determine whether it's sensible to take the whole loom out and replace with a minimal loom you will create, or you are just thinking about removing a few redundant wires.

Hey, pretty much everything said above (lights, wipers and fuel pump plus the engine electrics and cluster) I'm keeping, I've emailed the guys that run the BMW compact cup, asking for what the standard stuff that's usually taken out so I can get back to you with a bit more detail.

[Penelope Stopit]

If you know nothing about what you can and can't remove and how to get round the anti theft system and all other problems that may prevent the engine from running and the cluster from operating correctly.......If you pay someone to do this job they are going to charge you a small fortune, they are going to be spending many hours looking for information about what they can and can't remove and how to get round the anti theft system etc

Someone somewhere that races in the same series that you are going to be racing in has a list of what can and can't be removed, there is very likely a full set of instructions for the preperation of a BMW E36 for this series

I can easily put a list together for you that will show you what to keep for the front and rear lighting looms, the thing is that this is the easy part of the job

I recall that the E36 instrument cluster is programmed to the specific numbers that can be found attached to the base of the rear seat and I think that if the cluster or engine ECU are not of a programmed pair then the engine won't run

Another problem is that you don't mention anywhere about what cluster and ECU you will be using

This job could cost you anything from 3500 to 5000 if you drop the car off to someone and ask them to get on with it and will be money well spent if the cost isn't an issue

[Wazbeyondthewall]

Wow that’s a lot of money, my range would only be a couple hundred pounds, but I’m up for trial and error figuring it out aswell!

It’d be great if you could draw that up for me, emailed the guys over at the compact cup for more information on the wiring, they usually reply within a couple of days so I can get back to you with more detail.

https://www.bmwracedays.co.uk/product/superchip-co... This is what is mandatory to install, which I believe isn’t actually the ECU but something that plugs into it? If so it’d just be the standard ECU I’d be using.

Thanks!

[Penelope Stopit]

When does the job need completing by?

[GreenV8S]

Wazbeyondthewall said:

Yeah pretty much everything you've listed I'm keeping.

I understand you're stripping the car out to use it for racing. To start with I suggest you keep the loom as it is and just disconnect the switches and devices you no longer need. There may be sub-looms that are completely redundant which can be disconnected easily and it's worth removing those. You should either wrap or sleeve the loom for protection and it's easy enough to deal with loose ends when you do that.

This will be much, much easier and safer than cutting the loom down or building your own minimal loom from scratch. It does mean you're carrying several kilos of redundant wiring and connectors, but means you aren't breaking anything essential for the car to run - if you disconnected something you later find you need, you can always reconnect it.

Once it's running you will have a ton of issues to deal with and I suspect simplifying the wiring will be way down the list of priorities, but in due course you can go back and remove any redundant parts of the loom.

[Penelope Stopit]

I was going to email you but you don't allow messages
I get -

Oops...

Sorry - the recipient doesn't permit emails

[Wazbeyondthewall]

GreenV8S said:

Wazbeyondthewall said:

Yeah pretty much everything you've listed I'm keeping.

I understand you're stripping the car out to use it for racing. To start with I suggest you keep the loom as it is and just disconnect the switches and devices you no longer need. There may be sub-looms that are completely redundant which can be disconnected easily and it's worth removing those. You should either wrap or sleeve the loom for protection and it's easy enough to deal with loose ends when you do that.

This will be much, much easier and safer than cutting the loom down or building your own minimal loom from scratch. It does mean you're carrying several kilos of redundant wiring and connectors, but means you aren't breaking anything essential for the car to run - if you disconnected something you later find you need, you can always reconnect it.

Once it's running you will have a ton of issues to deal with and I suspect simplifying the wiring will be way down the list of priorities, but in due course you can go back and remove any redundant parts of the loom.

I may go with this option to begin with tbh, working on a semi-tight schedule so will save a lot of time.

[Wazbeyondthewall]

Penelope Stopit said:

I was going to email you but you don't allow messages
I get -

Oops...

Sorry - the recipient doesn't permit emails

Hey sorry about that, unsure how to get that to work

Edited by Wazbeyondthewall on Wednesday 25th July 15:19

[GreenV8S]

Recommend you take out the at symbol to reduce the risk of web crawlers harvesting your address.

[Penelope Stopit]

Penelope Stopit said:

When does the job need completing by?

Ok I've got your email address, thanks

I've looked into the problems you may have and also had a glance at the regulations....
It looks like you only need the drivers window motor working, I've not seen any mention of the passenger window so it can go unless you have more information than me

There is a mention of lights must all work but I don't know what the all is, I am guessing that all headlamps side lamps and indicators must work plus all rear lights

There is no mention about the horn but you may have more info

Wipers need to be working

There is no mention of door locks, you will benefit much by removing all the central locking system

EWS....This really is best left in unless you were planning on wiring in an EWS emulator, emulators could cause breakdowns and you don't want to be stopping when leading the race

Up to now it looks like you can rip out all the wiring from both doors and wire in a very simple circuit with a simple window switch to operate it

The radio aerial unit that connects to the heated rear window(HRW) can go and so can the suppressor unit that also connects to the HRW
If you want an HRW it can be wired direct to the wiring that is already there at the aerial unit
The HRW gadgetry that I mention above can be found in the C posts

Don't jump in with both feet, wait until you know exactly what must stay and what can go

The door wiring being ditched will save you a fair ammount of weight

All the sound system wiring can go

All the ABS wiring can go

I'm snowed under with an engine change and suspension rebuild right now

When does the job need completing by?

Edited by Penelope Stopit on Tuesday 24th July 19:24

[Penelope Stopit]

GreenV8S said:

Recommend you take out the at symbol to reduce the risk of web crawlers harvesting your address.

As above you can login and edit that post, remove your email address as I now have it

[Wazbeyondthewall]

Penelope Stopit said:

Penelope Stopit said:

When does the job need completing by?

Ok I've got your email address, thanks

I've looked into the problems you may have and also had a glance at the regulations....
It looks like you only need the drivers window motor working, I've not seen any mention of the passenger window so it can go unless you have more information than me

There is a mention of lights must all work but I don't know what the all is, I am guessing that all headlamps side lamps and indicators must work plus all rear lights

There is no mention about the horn but you may have more info

Wipers need to be working

There is no mention of door locks, you will benefit much by removing all the central locking system

EWS....This really is best left in unless you were planning on wiring in an EWS emulator, emulators could cause breakdowns and you don't want to be stopping when leading the race

Up to now it looks like you can rip out all the wiring from both doors and wire in a very simple circuit with a simple window switch to operate it

The radio aerial unit that connects to the heated rear window(HRW) can go and so can the suppressor unit that also connects to the HRW
If you want an HRW it can be wired direct to the wiring that is already there at the aerial unit
The HRW gadgetry that I mention above can be found in the C posts

Don't jump in with both feet, wait until you know exactly what must stay and what can go

The door wiring being ditched will save you a fair ammount of weight

All the sound system wiring can go

All the ABS wiring can go

I'm snowed under with an engine change and suspension rebuild right now

When does the job need completing by?

Edited by Penelope Stopit on Tuesday 24th July 19:24

Thank you very much for all the info! I'm looking to start the job around next week after I've thought through the options and had a look at the wiring in the car compared to the manual BMW provide for the car. I'll keep you posted. Thanks again!

[Penelope Stopit]

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