How To: E38/E39 Cruise Control and Multifunction Steering Wheel Retrofit to a '96 E36

[Bluebook]

E38/E39 Cruise Control and Multifunction Steering Wheel Retrofit to a '96 E36

I began by just wanting a new steering wheel for my car, as the one fitted was hideously worn and the leather was ripped, and it spiralled into a complete retrofit of E38/39 GR2 cruise control (I had no cruise fitted), an IBus nav radio and the aforementioned E38 MFL steering wheel. As these things do

But first - a disclaimer. My car is a Euro 03/96 320i six pot - essentially exactly the same as all six pot cars from that age, and this write-up can only be treated as accurate for those type of vehicles. Your four pot or diesel E36 may differ in some important areas, or it may not. I honestly don't know, as it was a hell of a lot of work just to research this retrofit, never mind taking in all the variants of the E36. Your experience may vary from mine, as they say.

All dates used are, to the best of my knowledge, production dates at BMW, not necessarily the year of the registration of the vehicle. Any part numbers quoted are Euro variants, though they may be World Wide - I didn't investigate that aspect. If in doubt, consult a dealer for info, and research through Real OEM.

First - Some History

E38/39 Multifunction Steering Wheels

From 12/95 to 09/96 the steering wheel controls connected to a separate control unit mounted under the dash via 3 wires, which sent out the IBus data on one wire and the cruise control data on another.

From 09/96 to 03/99 (end of production of the type of steering wheel and slipring that will fit an E36) all the electronics were moved into the button housings on the wheel itself, having IBus and cruise data outputs directly, with two slight variants.

1) From 09/96 to 09/97, the steeing wheel button for "cruise off" was marked with an "O" only, it was used with a separate "cruise on" switch on the dashboard.

2) From 09/97 to 03/99, the steering wheel button for "cruise on/off" was marked "I/O" and the separate "cruise on" switch was deleted.

I would recommend getting an MFL steering wheel from any production date fom 09/96 to 03/99, as they are much neater (having no separate decoder box) and because the good news is the code sent by the "O" button on the earlier 09/96-09/97 wheel to the GR2 brain is identical to the code sent by the "I/O" button on the later 09/97-03/99 wheel, the only difference being the printing on the button itself.

I have a MFL steering wheel from a 03/97 E38, and a GR2 brain from a 05/98 E39 fitted to my car, and it works perfectly.


GR2 Control Box (brain)

I only considered GR2 boxes made from 09/96 onward, to more closely match the MFL steering wheel I'd already purchased, so I have no information about the earlier brains. They may be similar, I just don't know.

From 09/96 on, they differ in two important ways (to this guide).

1) From 09/96 to 09/97 the brain used a separate "cruise on" switch on the dashboard. If you get one of these, you will need to source the "cruise on" switch too.

2) From 09/97 to 03/99 the separate "cruise on" switch was deleted, and all operations are controlled by the MFL steering wheel.

I would recommend getting a GR2 brain from 09/97 to 03/99, as again it's neater, not requiring the separate "cruise on" switch. The part number for the brain I got was 8 375 497.

But don't let that fool you, it's the same part number for pre - 09/97 brains as for post - 09/97 ones, it's the internal software that differs. The production date is the important thing.


Cruise Control Actuator/Motor

I think there were two different types fitted to the E38/39 between 12/95 and 03/99 - the earlier type had a round 7-pin connector, and the later type had an oval 7-pin connector. I didn't research the earlier type of actuator, as again I wanted one that more closely matched the ages of the items I had bought, to be safer.

The part number for the actuator I bought is 8 369 027.

I think the type changed on 03/96, but again, I'm not really sure.

I would recommend getting a later one with the oval type connector. Why? Because I know they definitely work

Try to buy a complete actuator, that includes the cable and the fittings at the end. The throttle body on my car came with dual-cams for both the throttle cable and the cruise actuator, and it fitted straight on.




The Wiring Diagram

Right - to the bones of the retrofit. Here is the wiring diagram I came up with. I have marked some connections with a * then a number. My notes will follow.



Notes

*1 Power supply.

This is the wire that runs from the engine fuse box, from F46, to the brake light switch at the brake pedal. It is a violet/yellow wire. I picked up the feed underneath the fuse box, but you could just as easily get the feed from the brake switch itself. Those guys with check-control and a 4-wire brake light switch - I'm pretty sure the colours are the same for the wire feeds you need, but please check wiring diagrams.

*2 Gear select input.

This only applies to cars with an auto box obviously, and I don't know if the autobox control unit (EGS) fitted to the E36 even has this output you could use - you will have to research this for yourself. All I know for sure is if you leave this connection open-circuit, the cruise brain will be enabled. I have a manual gearbox, and that's what I did.

*3 Cruise standby light.

To my knowledge, there was never a light in the instrument cluster to show the cruise is enabled on those E36s fitted with cruise as standard, but there was on the E38/39s, so I had to use it

I don't have Check Control fitted to my car, so I wired the output of the GR2 brain to pin 26 of the blue instrument cluster connector, X17. The Check Control idiot light now serves as my "cruise control enabled" light. Not perfect, I know, but good enough, until I think of something better

There are other options depending on what was fitted as standard to your car (in other words, which lights are not used) but be aware - not all of the unused ones can be used for this purpose. The light must have a direct output from the instrument cluster via one of the white x16 or blue x17 connector pins. Please consult the Bentley manual electrical diagram ELE-165 for further info. Some lights show a diode symbol in series with the connecting line - this is fine, as the bulbs in the instrument cluster have a common internal +12v supply, and the bulb is switched on by grounding the output pin. This seems to be how almost all of the lights are lit in the cluster, and works just fine with the GR2 brain.

*4 Clutch switch.

I haven't fitted one of these yet, but I will do, and recommend you do too. I have just grounded this line for the moment.

It isn't as dangerous as it may sound, as the GR2 brain has a rev signal input as a fail-safe, and constantly compares the rate of change of this signal to the rate of change of the speed signal it gets. If there is an obvious difference between the rates of change of these two signals (for instance, if you stamp on the clutch without hitting the brake) it cancels the cruise mode within 0.5 seconds. This equates to a rev rise of about 500 RPM only, so not really a problem.

It has annoyed me on a few occasions though, so it's best to fit one. I will be.

Obviously, those of you with auto boxes need not worry about this - just connect this line to ground permanently.

*5 "Cruise on" Dashboard switch

If you have a GR2 brain manufactured between 09/96 and 09/97, you will need one of these. It is a non-latching press switch that mometarily connects pin 22 of the GR2 brain to ground, to switch the cruise system into standby (ready) mode.

If you manage to find a GR2 brain from 09/97 or later, just leave this pin unconnected.


*6 Cruise Control Data Input

This line connects to pin 4 of the output connector of the slip ring of the MFL steering wheel.

What I don't know is anything about the earlier MFL steering wheels with the separate output box (12/95 - 09/96). This control box also has a cruise output line (pin 5 of X10171). Will this control the later GR2 brains? No idea.

But since it makes little sense to change control data protocols (even if you change the electronics that generate them) then it is a gamble. Your choice, I guess


*7 GR2 data line to EGS auto gearbox

This took me a good while to work out. I'm pretty sure this line sends data to the auto box to tell it the cruise is enabled. As far as I can gather, it's to stop the EGS autobox brain from making annoying upchanges/downchanges when the cruise system is operating.

This definitely applies to the EGS system in the E38/39, and I'm pretty sure it tells the EGS brain to load a different shift programme (like sport, winter etc) but one taliored for the cruise mode.

I have no idea whether anything like this is available in the EGS system of the E36, I just left it open circuit as I have a manual gearbox.



And I think that's about all I have. It was a big project, but very much worth doing.

Hope it's helpful.

[downeaster1]

Holy cow. Good write up man!

[Joylove]

Bump for an amazing writeup.

Edit: So I guess a multi-wire wheel is mandatory, as is a multi wire slip ring? 7 wires?

How did you find out the produciton date for the CC module?

[erjfly2013]

Forgive me, but i've been researching this for some time.
I have an e36 produced 12/97.
Does it have an Ibus? Is the steering wheel plugged into anything now (airbag and horn) like an Ibus? Where can i get an Ibus from to complete this mod? I already have cruise on my model. Do i need a different "slip ring"?
Thanks.

[Joylove]

You have an ibus that connects to the CD changer and the radio only.

The slip ring is 4 loose wires. You need the E39 7 wires for the pre 99 MFSW. After 1999 the steering wheels and slip rings are totally incompatible.

To complete this mod you must undergo the steps regarding chaning the ECU, the wheel, the slipring and the wiring to the cluster.

[Bluebook]

Bump for an amazing writeup.

Edit: So I guess a multi-wire wheel is mandatory, as is a multi wire slip ring? 7 wires?

How did you find out the produciton date for the CC module?

Yep, you will need to obtain a steering wheel with the buttons already present, much easier that way.

It may be possible to retrofit button pods to some of the last M-style wheels fitted to an E36 (as visually, they closely resemble early E46 wheels that have MFL capability) but I bought a MFL steering wheel with the slipring still attached. Easier all 'round.

I emailed the ebay vendors to ask the production dates of the items I bought - all had good records of the ages of the donor cars, or still had the cars to refer to the production date sticker under the bonnet.

Forgive me, but i've been researching this for some time.
I have an e36 produced 12/97.
Does it have an Ibus? Is the steering wheel plugged into anything now (airbag and horn) like an Ibus? Where can i get an Ibus from to complete this mod? I already have cruise on my model. Do i need a different "slip ring"?
Thanks.

If you have a factory fitted CD changer, then you have an IBus radio, most likely. If not, you may have to obtain an IBus radio, as I did.

You will need to get a complete MFL wheel and slipring, as there aren't enough connections in the standard E36 slipring.

[Joylove]

I emailed the ebay vendors to ask the production dates of the items I bought - all had good records of the ages of the donor cars, or still had the cars to refer to the production date sticker under the bonnet.

OK, so if you only had access to the HW and SW version, could you figure out if the module was suitable?

[Bluebook]

OK, so if you only had access to the HW and SW version, could you figure out if the module was suitable?

Well, if you could find a friend at a local BMW dealership, or perhaps mail BMW direct, you could get an answer to that.

I don't know those numbers myself.

I just used the production dates.

[Wocka]

Hello,

Just doing this retrofit myself, very helpfull information, thanks very much.

Does anyone know what happens if you dont connect the RPM wire? My module's plug doesn't have a wire for pin 8.

Thanks

[Wocka]

Hello,

Just doing this retrofit, very helpfull info above, thanks very much.

Does anyone know what happens if you don't connect the RPM wire? My module's plug doesn't have a wire for pin8... it came off an automatic.

Thanks

[M3C]

Got any pictures after completed.

[Bluebook]

Sorry for the quality, phone camera.

[M3C]

That is cool picture, I see you got the Traffic Pro too.
Do your steering wheel control buttons illuminate all the time when car engine is running or only when lights are on?

[Bluebook]

That is cool picture, I see you got the Traffic Pro too.
Do your steering wheel control buttons illuminate all the time when car engine is running or only when lights are on?

I used to have a Becker 7944 Cascade unit in the car; much, much better head unit. Bluetooth, flash card nav data, so much quicker. But since Becker (in their infinite wisdom) decided not to make that radio IBus compatible, I had to ditch it in favour of the old Traffic Pro. Still does the job, though.

The wheel I have is from a 03/97 E38 - the type without a separate decoder box under the dash. So there is no separate line for illumination into the wheel itself, unlike the 12/95 - 09/96 E38/9 wheels. So the power line automatically illuminates the buttons. They are lit all the time.

I wired the MFL power line to the accessory 12V output of the head unit, because it's possible to turn on the Traffic Pro without any key in the ignition. So the buttons work when the radio is on.

That's not quite it for the power connection - I also wired the ACC ignition power to the same line via a diode, so if you happen to turn the radio off while driving (or the radio fails) the buttons will still have power, and operate the cruise.

[M3C]

Nice to hear you're happy with BMW TP, I have the same unit made by Becker, believe the only difference is the model as this one is for US model 4771, most likely your's is 4773 which is for Europe if I'm not mistaken. But the functions and the looks are the same.
Have same control functions but my steering wheel is M 3 spoke and buttons are set to illuminate when the engine is running (radio on or off).
How did you exactly made the wiring with a diode to have power for cruise functions if radio fails?

[Bluebook]

Here is a quick sketch that should explain things...



I didn't explain myself very well yesterday - I forgot I put two diodes in, not one.

They are there to stop the radio trying to power the whole car's accessory circuit if you switch the radio on without the key in the ign, and the diode inline with the radio's acc output is just belt-and-braces really - if you have the ign on, and the radio off, feeding 12V back into the radio's acc circuits may cause something to go bang. So better safe than sorry!

[vlakci]

DIN size ibus compatible radios are:
- BMW Business CD (model CD43)
- Rover CD radio (model CD43 - same as BMW type only some differenty fonts on the buttons signs)
- BMW C Professional (only becker model BE2455 - the old model BE2450 is not compatible! A big + is that the BE2455 is compatible with Mbus and Ibus changers)
- USA casette (C43)
- Becker Traffic Pro

Or get and adapter to convert Ibus orders to Pioneer/Sony/Alpine remote inputs.

I did this modification some time ago and it works perfectly (MFL, BMW phone, CD43 radio, HK 12 speaker setup, Dension USB interface ).

[MParallel]

....I did this modification some time ago and it works perfectly (MFL, BMW phone, CD43 radio, HK 12 speaker setup, Dension USB interface ).

Vlakci, 12 speaker HK? Did you install 2 extra speakers?

2 in front door + 2 in rear panel = 4
Same on both sides: 4x2 = 8

2 footwell speakers: 8+2=10

+ a subwoofer.

If you count the sub as a speaker, you have 11. What is the 12th speaker?

[Bluebook]

Vlakci, 12 speaker HK? Did you install 2 extra speakers?

2 in front door + 2 in rear panel = 4
Same on both sides: 4x2 = 8

2 footwell speakers: 8+2=10

+ a subwoofer.

If you count the sub as a speaker, you have 11. What is the 12th speaker?

The factory HK system was 10 speakers, with an 8-channel amp.

2 x kick-panel 130mm on 2 channels front
2 x 65mm mids and 2 x 19mm tweeters on 2 channels front
2 x 16x9 woofers on 2 channels rear parcel shelf
2 x 65mm in same 16x9 moulding rear parcel shelf

The E36 was before my time working at Harman, but almost the same system was used on the early E46, which I worked on extensively.

[Joylove]

Thanks for this pioneering guide. I plaguerised it extensively to write mine.

[Bluebook]

Thanks for this pioneering guide. I plaguerised it extensively to write mine.

De nada.

[MParallel]

The factory HK system was 10 speakers, with an 8-channel amp.

2 x kick-panel 130mm on 2 channels front
2 x 65mm mids and 2 x 19mm tweeters on 2 channels front
2 x 16x9 woofers on 2 channels rear parcel shelf
2 x 65mm in same 16x9 moulding rear parcel shelf

The E36 was before my time working at Harman, but almost the same system was used on the early E46, which I worked on extensively.

It was a bit of a rhetorical comment.

What you list however is the setup for a coupe.

The E36 vert, as it has no parcel shelf (this is the softtop compartment cover) the E36 vert has a mid/tweet located behind the rear "door"cards

This is a single housing, with only one + an - wire going to both. A filter in the wiring is used on the tweet. I take it this is a singe channel to run 2 speakers.

Also, the vert has a unique separate subwoofer in the skihatch, with 2x + and - wires going to it. No sure how this works. Dual coil maybe?

I'm no audiophile so I take it a single +/- is a channel?

Front footwell speakers only have a single +/- connection. Unless you mean x2 for a side, so making 2 channels.

In that case the doorcard speakers are 4 channels. There is a dedicated +/- wire for each speaker in the doorcard.

So that would mean (if I'm anything near correct) that the E36 vert amp has 10 channels.

footwell speakers 2 (one each side)
doorcard mid/tweet 4 (two on each side)
rear mid/tweet 2 (one shared connection on each side)
sub 2 (single unit, 4 connections).

[Bluebook]

It was a bit of a rhetorical comment.

What you list however is the setup for a coupe.

The E36 vert, as it has no parcel shelf (this is the softtop compartment cover) the E36 vert has a mid/tweet located behind the rear "door"cards

This is a single housing, with only one + an - wire going to both. A filter in the wiring is used on the tweet. I take it this is a singe channel to run 2 speakers.

Also, the vert has a unique separate subwoofer in the skihatch, with 2x + and - wires going to it. No sure how this works. Dual coil maybe?

I'm no audiophile so I take it a single +/- is a channel?

Front footwell speakers only have a single +/- connection. Unless you mean x2 for a side, so making 2 channels.

In that case the doorcard speakers are 4 channels. There is a dedicated +/- wire for each speaker in the doorcard.

So that would mean (if I'm anything near correct) that the E36 vert amp has 10 channels.
footwell speakers 2 (one each side)
doorcard mid/tweet 4 (two on each side)
rear mid/tweet 2 (one shared connection on each side)
sub 2 (single unit, 4 connections).

Yes, each speaker in the doorcard had a dedicated wire, but the 65mm midrange and the 19mm tweeter were connected to the same channel of the amp. They were connected to each other somewhere in the door harness, I think. It's a very long time since I worked on the HK system!

HK only ever produced an 8 channel amp for the E36.

You are right about the rest though - in my defence, I only ever worked on the saloon and the coupe.

[Joylove]

Well, if you could find a friend at a local BMW dealership, or perhaps mail BMW direct, you could get an answer to that.

I don't know those numbers myself.

I just used the production dates.

Do you have time or some pictures to check your CC module version? There is some discussion that HW08 SW04 is the minimum standard for modules to not need the MFL module. Thanks

[MParallel]

Yes, each speaker in the doorcard had a dedicated wire, but the 65mm midrange and the 19mm tweeter were connected to the same channel of the amp. They were connected to each other somewhere in the door harness, I think. It's a very long time since I worked on the HK system!

HK only ever produced an 8 channel amp for the E36.

You are right about the rest though - in my defence, I only ever worked on the saloon and the coupe.

Not sure if you mean this, but just for the record:

The midrange and tweeter in the (front) doorcards have dedicated wires, that go to a single connector at the doorhinge. However, this connector has 2x2 pins inside it, so both speakers have dedicated +/- wires going all the way back to the amp. Whether this is equal to 2 channels or 1 I don't know.

So the doorcard speakers have dedicated wires, the footwell woofers have dedicated wires, the rear midrange/tweeter pod has a single set of wires and a filter in the wire to the tweeter filters tones (funny enough I have seen the non-H/K Hi-Fi setup, and here the rear speakers do have dedicated wires for both) and the sub has 4 dedicated wires.