smarty156

I have an M5 wheel (pre- Sept 05) with slip ring and custom loom that Hobi (I believe) made so that the paddle shifts will work on the steptronic auto.
The M5 wheel came with the small black box ecu included and all the original wiring to it as well as the customised wiring.
The customised wiring has plugs for the paddle shifts. The wheel originally had nothing plugged into the multi function sockets therefore I need to plug in something to these to get them to work.
Question is, do I take the ecu from my original standard wheel (with hexagonal airbag) with the multifunction wiring and put that in the M5 wheel in place of the original M5 ecu and wiring (which had multifunction and paddle shift wiring included on one loom)? Or do I use my original ecu with the M5 wiring? Or the M5 ecu with my orignal multifunction only wiring?
Obviously I am changing the airbag from a hexagonal one to a round one and this plugs into the wheel ECU. So do I need to make sure the ecu and airbag stay together to avoid having to get it re-coded or do I connect the round airbag to my ecu? Will this then mean I need to get it recoded?

I tried to install the wheel yesterday. I used my original wheel ecu and multifunction wiring in the M5 wheel with the round airbag. When I reconnected the battery I got a "Restraint system failure" warning. The multi function buttons worked fine and the paddle shifts changed the gears (albeit the up shifter made it shift down and the down shifter made it change up!).

I've now put the original wheel back as it was but I still have the "Restraint system failure" warning.

Please help!

PS I spoke to a BMW dealer today about changing my standard wheel to an M Sport wheel to see what they said I needed. They said all I needed was the wheel and airbag plus an hour and a half fitting which included re-coding the airbag. This makes me think there's actually nothing wrong with the restraint system and it just needs the airbag re-coding when I change it. However, from what I've seen and been told, no-one who has done this install has had to have the airbag re-coded. I am really confused!!!!

AlexFW

Come on, someone help him!

radioham

i think you should have used the m5 complete wheel ecu airbag and left it at that.now it could be you have a fault logged and it will need turning off by the computor .as it has seen a change that was not compatible. and although you have reverted it will still display fault message.
try and email my530i i am sure hewill be able to help you.
there is the info in hobi posts regarding this issue, so read through them as well.

bruce_miranda

The airbags a very sensitive and once they raise a fault they will stay that way until the dealer resets them. You can buy a device on the web/ebay that will allow you to reset airbag warnings.

thanhe60

did you disconected the + on your bettery? if so it will need to re-coded.
when changing out the streering wheel you just need to disconect the negative -
on the bettery and DO NOT turn on the key.

andy545

1. Did you disconnect the battery when you did this? <<<<<
2. The M5's sw ecu would have been fine. You bridge the custom loom onto the existing steering wheel wiring. The custom loom already has the smg plugs ready. The original M5 smg plugs are left dormant.

I recently finished this mod even modifying it (with the help of nicke60gre) to get the steering wheel heating working as well.
no probs, first try worked perfectly.

smarty156

Thanks for the replies everyone.

Yes, I disconnected the negative battery terminal and followed all instructions as per my530i's DVD. Problem is, this started with a completed wheel and the guy I got the wheel from couldn't remember exactly what went where as Hobi inbstalled it for him about 3 years ago! Although he did say I needed to swap the ecu's over so that my original one was still used in the car - I guess not!

I've got the car booked in at the dealer on Wednesday to get the fault cleared.

So, just to be clear, I should use the M5 wheel ecu with the M5 airbag? This will then mean I don't have to get the airbag recoded and there will be no faults? I'm guessing using the original ecu and new airbag (which causes a fault) could be resolved by getting the dealer to re-code the airbag to ecu?
Re the wiring for the multi function buttons/paddles, I guess I can either use my original wiring that just has the multi function connectors (as the custom loom already plugs into the paddles) OR use the M5 wiring and just leave the paddle shift plugs unplugged?

I did read all of Hobi's posts on this but there's no mention of the wheel ecu or multi-function wiring. There's a link to his website that may have had more detail but it's no longer operative.

I also have the + and - paddles operating back to front at the moment (- changes up and vice versa). Maybe it's because I'm using my existing wiring and not the M5 wiring? Can't understand what else it would be as all the connectors can only plug in one way. Any thoughts?

Thanks again everyone.

smarty156

Thanks for the help.
I have sent my530i a PM but no reply yet.
I read all of Hobi's posts but there's no mention of the ecu or multi function wiring as far as I can see.
Yes, I realise the fault will stay logged but I have reverted back to original so that I can get the dealer to clear the fault and hopefully they will do it under warranty as they won't know it was me that caused it!

smarty156

No, I disconnected the negative terminal only and didn't turn the key until after it was all back together.

Craggy

I did this mod on my 545i, I took off my original hexagon wheel, airbag etc and replacen it with an M3 SMG wheel from an E46 and it worked fine. I kept the original ecu in the wheel from the hexagonal wheel and the rest was E46 parts. No airbag recoding was necessary even with an airbag from a different series.
If you get a restraints system failure with your original ecu still connected then the problem must have been that the battery was reconnected at some stage with that module disconnected, even for a split second and it will give a fault. This fault is a permenant fault and must be cleared by BMW even if you reconnect everything it wont go away...