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e34iT
10-16-2020, 08:04 PM
Hi,

I'm looking into doing a multifunction steering wheel upgrade to my '95 e34 touring. Found this link: http://www.frankies-bmw.com/8series/diy/mf_wheel/bmw_8series_mf_wheel.php

My steering wheel is in good shape, so I'm trying to figure out if there's a way to use my steering wheel with the 97-99 e38/e39 slip ring and airbag? Everything I find for sale is in bad shape.
I found the part numbers on realOEM:

My steering wheel: 32341162110
My slip ring: 32341162111
My airbag: 32341093308

Newer steering wheel: 32341094259
Newer slip ring: 32341094261
Newer airbag: 32346753716 or 32341097125?

Both steering wheels seem to need the same 32341097110 screws to mount the slip ring to the wheel, so it seems like I might be able to swap my wheel's slip ring. Not sure though.

It says that slip ring 261 will directly swap onto a 95-on car with slip ring 111, so I am good to directly swap wheels. I just can't figure out if I can keep my wheel and put the multifunction slip ring and airbag onto it? Any ideas?



Thanks


Update: Both steering wheels seem to need the same 32341097110 screws to mount the slip ring to the wheel, so it seems like I might be able to swap my wheel's slip ring. Not sure how I can confirm this without trying, but slip rings are very expensive so trying to confirm beforehand.

zkd
10-17-2020, 02:30 PM
yes you can upgrade and you can use slip ring from e39 up to 97.

the question is do you want for show or functional?

if you want function then you need a CD43 head unit and have the wire from pin 7 on the head unit go directly to the slip ring. then the audio function will run fine. (but you have to cut the wire from the rest of the car.)

if you want cruise control to work, then you have 2 options:- (assuming you have cruise control in the car)

1- google for an interface for converting the Steering wheel signal to the e34 signals. (I have not found one but they are around)

2- you can use the cruise control unit from an e39/38 up to year 97 but you have to match the wiring....

you well also need to connect power and ground to it. horn and airbag are standard...

that's about it.... hope it goes well.

e34iT
10-18-2020, 05:40 PM
yes you can upgrade and you can use slip ring from e39 up to 97.

the question is do you want for show or functional?

if you want function then you need a CD43 head unit and have the wire from pin 7 on the head unit go directly to the slip ring. then the audio function will run fine. (but you have to cut the wire from the rest of the car.)

if you want cruise control to work, then you have 2 options:- (assuming you have cruise control in the car)

1- google for an interface for converting the Steering wheel signal to the e34 signals. (I have not found one but they are around)

2- you can use the cruise control unit from an e39/38 up to year 97 but you have to match the wiring....

you well also need to connect power and ground to it. horn and airbag are standard...

that's about it.... hope it goes well.


Thanks for the info. Going to get an aftermarket head unit actually. The question is I'm trying to use my old steering wheel with the multifunction parts since it's in good condition. So I want to use my 95 steering wheel with 97-99 airbag and slip ring. Is this possible?

Thanks

zkd
10-19-2020, 02:58 PM
As I said up to 97 since after that the airbag changed and the connectors will not match also some of the newer ones the slip ring is mounted on the column rather than the steering

Singing6
11-12-2020, 05:21 PM
There is some missing info here. As ZKD mentioned, the multifunction wheel will not talk to a stock E34 radio. The E34 uses a two line serial communication (LAC and DAC lines) system. The e36 swapped from this to the i-bus system that the E38 and E39 used in 1996. I don't know enough about the E31 to speak on it but at some point it must have had a little bit of I-bus in it. I-bus is a single line serial communication system btw.

The multifunction steering wheel is I-bus based. It can only talk to other I-bus modules. There are none of these in any factory E34. The C43 and CD43 head-units from the E36 however, do have I-bus (there are likely others, but this is all I can think of off hand). As do their trunk CD players. If you want to use the multifunction steering wheel, you need to have other I-bus capable components. In this case, the cruise control module and the head-unit. I have not actually thought of swapping an e39 cruise control module into an E34, but I will be looking into it now.

As for converting I-bus to the two line serial: nothing currently exists on the market. Hell, there are only a handful of people on this forum who can even talk on the LAC/DAC serial system. I am about 90% of the way to a functional system, but information is scarce on this stuff.

If you are going aftermarket radio, you best hope it has some CAN Bus on it, because the only converters out there are i-bus to CAN-bus. But I also make no assurances that that will even work. Otherwise, just get a C43 or CD43. Or don't bother with the multifunction wheel.

With airbags: the changeover that is an issue is when BMW switched to a two-stage airbag. These worked by having two explosive charges that were fired separately. The delay between the two firings determined how fast the airbag would deploy. Obviously the E34 was not ever equipped with this. TL; DR: The airbag must have only 2 pins on the electrical connector, a 4 pin will not work.

My advise on the cruise control would be that you translate the I-bus signals with an Arduino to an analog 12v output with big transistors or some small relays to simulate the action of the E34 cruise control stalk. This is what I will be doing as soon as I decode the I-bus outputs from the steering wheel (I have one of the wheels on its way in the mail).

TiagE39
11-19-2020, 10:37 PM
Just wanted to add this since I've bench worked both C43 and CD43 radio units: only the CD43 is an I-bus capable head unit. C43 is not, it uses "M-Bus" which is a completely different standard (and not compatible). Any CD43 will work, whether it is the ///M "counterfeit" one (really a Rover Group unit) or the genuine "BMW Business" unit (Rover adopted I-bus on their cars while under BMW ownership). There are of course many other I-bus capable head units out there, but most are Euro-only and very difficult/expensive to source.

Other than that, the rest is accurate: you'll need to connect Pin 7 on the radio connector to an E38/E39 multifunction steering wheel column harness

Changeover to dual-stage airbags on E38/E39's was in March 1999. You can easily tell single from dual-stage by the slip ring placement. Slip ring stays with the wheel on single stage, but lives on the steering column with dual stage. A dual stage wheel will NOT work or fit.

zkd
11-21-2020, 04:29 AM
Just wanted to add this since I've bench worked both C43 and CD43 radio units: only the CD43 is an I-bus capable head unit. C43 is not, it uses "M-Bus" which is a completely different standard (and not compatible). Any CD43 will work, whether it is the ///M "counterfeit" one (really a Rover Group unit) or the genuine "BMW Business" unit (Rover adopted I-bus on their cars while under BMW ownership). There are of course many other I-bus capable head units out there, but most are Euro-only and very difficult/expensive to source.

Other than that, the rest is accurate: you'll need to connect Pin 7 on the radio connector to an E38/E39 multifunction steering wheel column harness

Changeover to dual-stage airbags on E38/E39's was in March 1999. You can easily tell single from dual-stage by the slip ring placement. Slip ring stays with the wheel on single stage, but lives on the steering column with dual stage. A dual stage wheel will NOT work or fit.

The C43 has M-Bus but it doesn't work with MF-Steering wheels, the C33 however does, it is basically same as C43 but without RDS.

TiagE39
11-23-2020, 02:52 PM
Nope, C33 isn't an I-bus radio either.

Singing6
12-07-2020, 04:50 PM
Found a fantastic guide that shows how to fit a dual stage airbag wheel onto a single stage car:

http://www.frankies-bmw.com/8series/diy/mf_wheel/bmw_8series_mf_wheel.php

e34iT
12-30-2020, 10:22 PM
Sorry- I lost my password and haven’t been active in a while. Thanks for the info. I was trying to follow that same guide from Frankie’s BMW but am having a hard time finding a nice oem stock steering wheel from a 97-99 e39/8. Since my e34 is a 95 I was trying to see if I could use my good condition stock steering wheel with a multifunction airbag and clockspring. Do you think that would be possible?

Thanks

Singing6
01-08-2021, 11:45 PM
Uhhh. Maybe. Why don’t you try and make a post if it works!


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