Moving "DS" mode to steering wheel button

mkramer37 · 12-19-2016, 12:10 AM

There is one CAN module in the MFB's in the steering wheel. This is some sort of microcontroller that communicates over the K-CAN bus. Most likely, each button is a switch that connected a signal to ground when pressed. This signal is then connected to the microcontroller to transmit the data over the CAN bus that the button was pressed.

It could be possible to solder on a wire to the PCB of the MFB CAN module to to get the raw output of when the button is pressed. The only issue is that there are only 6 pins on the normal steering column to connect to. 4 of them are used by the CAN bus, and 2 of them are used for the paddle shifters. Since data is already being sent over CAN when a button is pressed, I think it would be eaiser to add your own CAN arduino module to receive it, instead of trying to figure out how to add more pins to the steering wheel connector...

mkramer37 · 12-19-2016, 12:23 AM

Quote:

Originally Posted by mad1stgen

Heated steering wheel option gives you two more wires. Not sure if clockspring is different in cars with a heated wheel ?

That is a very good idea. Yes there is a different part for the "switch unit steering column" when you have the heated steering wheel option. This would allows you to route more than 6 pins through the clock spring.

matteblue3er · 12-19-2016, 12:24 AM

Yea that module is the SZL.

The MFBs ground circuits to the SZL. The SZL then reports switch status over CAN.

What the OP needs to do is re-route wiring from the MFB he wants to use to a pancake slip ring, then to the DS circuit.

Of course integrating that slip ring will be a challenge and you have to worry about wear in this application. Personally, I'd machine a channel out of the steering wheel, place a slip ring in that channel, and have a small contact (maybe a ball bearing type contact to reduce wear) sticking out of the SZL to make contact with the slip ring.

mkramer37 · 12-19-2016, 12:44 AM

I feel like adding an arduino would be 100x eaiser than trying to manually add another pin to the clock spring, unless he gets the heated steering wheel trick working.

matteblue3er · 12-19-2016, 01:00 AM

If you use an arduino to inject a message into the CAN bus, you still need a way to tell that arduino to inject the message.

If he wants to use the steering wheel button, he would still need to run wires from the steering wheel to the column.

mkramer37 · 12-19-2016, 01:07 AM

The arduino would just passively receive messages, and would be located under the glove box. There are already wires connecting the buttons to the SZL, the car came with them already wired.

matteblue3er · 12-19-2016, 01:11 AM

Ahh I get what your saving. Have the arduino sniff the bus for the switch press

dstrickland · 12-19-2016, 09:26 AM

I'm past how to activate the DS mode. I've wired it to the push function of the paddle. The issue at hand now is how to route the extra wire through the slip ring.

I've searched for the slip ring, it seems the one they use for the digital performance steering wheel is suppose to have two 12 pin connectors in the back & an additional 3 pins in the front behind the airbag. When looking at the part number, it's the same one used on the e70 with heated steering wheel. But when I look at pictures of it on ecs or anywhere I can buy it, it has the extra 3 wires in front, but the back is still only 1-6pin & 1-12pin.

mkramer37 · 12-19-2016, 12:44 PM

Quote:

Originally Posted by dstrickland

I'm past how to activate the DS mode. I've wired it to the push function of the paddle. The issue at hand now is how to route the extra wire through the slip ring.

I've searched for the slip ring, it seems the one they use for the digital performance steering wheel is suppose to have two 12 pin connectors in the back & an additional 3 pins in the front behind the airbag. When looking at the part number, it's the same one used on the e70 with heated steering wheel. But when I look at pictures of it on ecs or anywhere I can buy it, it has the extra 3 wires in front, but the back is still only 1-6pin & 1-12pin.

Yeah, the digital performance steering wheel is most likely on the CAN bus, so it doesn't use any more pins on the back of the steering column. Also, the heated steering wheel probably doesn't use any more pins since the button to enable it is on the steering column. You would have to open up the slipring, cut the heated steering wheel wires, and route them yourself, not in the 12-pin connector.

As you can see, it would be pretty difficult to route more pins through the slip ring, which is why I am suggesting having an arduino sniff the CAN bus for a MFB press and send the signal to activate DS mode.

mad1stgen · 12-19-2016, 01:56 PM

Clock spring part number 61319169765 directly from my car with a heated wheel.
It has an extra blue connector, with 4 wires, on the wheel side.

and then ...

http://www.e90post.com/forums/showth...=501185&page=2

dstrickland · 12-19-2016, 05:56 PM

Quote:

Originally Posted by mad1stgen

Clock spring part number 61319169765 directly from my car with a heated wheel.
It has an extra blue connector, with 4 wires, on the wheel side.

[img]https://c1552172.ssl.cf0.rackcdn.com/499580_x800.jpg[/img]

and then ...

http://www.e90post.com/forums/showth...amp;amp;page=2

This doesn't help. It may have an extra 4 in the front, but it still only has 18 total going out the back, 1-6pin & 1-12pin. Meaning the heated steering function is being triggered by CAN as well.

I can use the pins in the front to wire DS mode, but with nowhere in the back to come out of to go the the gear selector it's no good.

The Arduino sounds like a solution, but it sounds out of my league programming side.

All 18 of my pins are in use.

matteblue3er · 12-19-2016, 09:15 PM

I'm not sure about this but is there more than one horn button?

Maybe repurpose one

dstrickland · 12-19-2016, 09:22 PM

Quote:

Originally Posted by matteblue3er

I'm not sure about this but is there more than one horn button?

Maybe repurpose one

No, the horn is triggered by pressing in the airbag. I've considered using the pin for the horn & moving the horn trigger elsewhere.

I definitely use sport mode more than the horn. I may use that thing twice a year, and use sport mode every day. Will probably go that route if I can't figure it out.

mad1stgen · 12-19-2016, 10:06 PM

Quote:

Originally Posted by dstrickland

All 18 of my pins are in use.

Sorry, I wasn't aware of that.

Maybe it's possible to implement the heated wheel circuit to work as a pass thru for your sport switch signal ? It does have an analog switch on the column side.

People are able to retrofit the heated wheel without any coding, so I don't think CAN BUS plays a big role in it.

dstrickland · 12-19-2016, 10:10 PM

I think I've found my solution, and it will free up 2 pins leaving me with an extra slot in case I want to do something else.

I'm going to use only one stage of the dual stage airbag(if it wasn't safe, America wouldn't be the only country that uses them). If I wasn't the only driver of my car I would reconsider. The airbag takes a total of 4 pins on the wheel side & another 4 on the back side of the slip ring, one negative & one positive for each stage.

mkramer37 · 12-20-2016, 12:12 AM

Quote:

Originally Posted by dstrickland

I think I've found my solution, and it will free up 2 pins leaving me with an extra slot in case I want to do something else.

I'm going to use only one stage of the dual stage airbag(if it wasn't safe, America wouldn't be the only country that uses them). If I wasn't the only driver of my car I would reconsider. The airbag takes a total of 4 pins on the wheel side & another 4 on the back side of the slip ring, one negative & one positive for each stage.

That is a fucking terrible idea. A single stage airbag might be as safe as a dual, but you can't just turn a dual stage airbag into a single stage by unplugging one the the connectors. A dual-stage airbag will not function properly without both detonations...

You'll throw codes from not having an airbag connected and will not pass safety inspections

dstrickland · 12-20-2016, 08:10 AM

Quote:

Originally Posted by mkramer37

Quote:

Originally Posted by dstrickland

I think I've found my solution, and it will free up 2 pins leaving me with an extra slot in case I want to do something else.

I'm going to use only one stage of the dual stage airbag(if it wasn't safe, America wouldn't be the only country that uses them). If I wasn't the only driver of my car I would reconsider. The airbag takes a total of 4 pins on the wheel side & another 4 on the back side of the slip ring, one negative & one positive for each stage.

That is a fucking terrible idea. A single stage airbag might be as safe as a dual, but you can't just turn a dual stage airbag into a single stage by unplugging one the the connectors. A dual-stage airbag will not function properly without both detonations...

You'll throw codes from not having an airbag connected and will not pass safety inspections

Each stage of the airbag works on it own circuit, disconnecting the 2nd stage will not effect the first stage of deployment at all. I replace detonated airbags 15+ times a week & am familiar with the internal of the airbag itself.

As for codes & safety inspections that's extremely simple. You can manually turn off the 2nd stage in the ACSM module & tell the car you only have one stage installed by changing 2 simple parameters. You can view my DIY for dual to single stage conversion on bimmerfest I wrote back in August for the F-series guys.

Install Euro Single Stage Airbag to USA Car http://www.bimmerfest.com/forums/sho...d.php?t=924625

90% of the sport wheel retrofits I do from e46 to G11's require me coding the car to single stage airbag due to people buying their airbags off eBay & getting single stages from Europe.

dstrickland · 12-20-2016, 08:21 PM

Bmw definitely doesn't like people playing with the airbags. They did they're best to confuse the people working on them.

Once pulling out the airbag, I took note that the stage 1 side was connected with yellow wires, one with brown stripe & the other with black stripe, the same with the stage 2 side except the wires were grey.

Once I disconnected the grey pins to the stage 2 side, I pulled the connector on the rear side of the clock spring. Was happy for a second when I saw that everything was colored just like the steering wheel side.

BMW's first switch up is that the black striped pins are actually the positive, the brown stripes are negative. The 2nd switch up is the stage 2 grey wires on the wheel side come out to the yellow wires on the backside, stage one's yellow wires come out to the grey side on the back.

I pulled the grey wires out the back of the connector & plugged everything back in, then noticed I had codes for stage 1 & 2. Plugged the grey wires back in, stage 1 cleared. Then I pulled the yellow wires out the back & stage 1 stayed gone.

Coded the airbag as a stage 1 only airbag & the lights gone. I now have 2 extra pins to connect to the slip ring, one goes to the the DS mode, the 2nd is yet to be determined.

My ideal paddle retrofit is complete. I can activate sport, standard drive, upshift & downshift with the flick of a paddle.

12-19-2016, 12:10 AM	#23
mkramer37 New Member 0 Rep 12 Posts Drives: 2011 328i xDrive Join Date: Aug 2016 Location: McLean, VA iTrader: (1)	There is one CAN module in the MFB's in the steering wheel. This is some sort of microcontroller that communicates over the K-CAN bus. Most likely, each button is a switch that connected a signal to ground when pressed. This signal is then connected to the microcontroller to transmit the data over the CAN bus that the button was pressed. It could be possible to solder on a wire to the PCB of the MFB CAN module to to get the raw output of when the button is pressed. The only issue is that there are only 6 pins on the normal steering column to connect to. 4 of them are used by the CAN bus, and 2 of them are used for the paddle shifters. Since data is already being sent over CAN when a button is pressed, I think it would be eaiser to add your own CAN arduino module to receive it, instead of trying to figure out how to add more pins to the steering wheel connector...
	Appreciate 0 Quote

12-19-2016, 12:24 AM	#25
matteblue3er Captain 243 Rep 949 Posts Drives: Racecar Join Date: Jul 2015 Location: Philly iTrader: (0)	Yea that module is the SZL. The MFBs ground circuits to the SZL. The SZL then reports switch status over CAN. What the OP needs to do is re-route wiring from the MFB he wants to use to a pancake slip ring, then to the DS circuit. Of course integrating that slip ring will be a challenge and you have to worry about wear in this application. Personally, I'd machine a channel out of the steering wheel, place a slip ring in that channel, and have a small contact (maybe a ball bearing type contact to reduce wear) sticking out of the SZL to make contact with the slip ring.
	Appreciate 0 Quote

12-19-2016, 12:44 AM	#26
mkramer37 New Member 0 Rep 12 Posts Drives: 2011 328i xDrive Join Date: Aug 2016 Location: McLean, VA iTrader: (1)	I feel like adding an arduino would be 100x eaiser than trying to manually add another pin to the clock spring, unless he gets the heated steering wheel trick working.
	Appreciate 0 Quote

12-19-2016, 01:00 AM	#27
matteblue3er Captain 243 Rep 949 Posts Drives: Racecar Join Date: Jul 2015 Location: Philly iTrader: (0)	If you use an arduino to inject a message into the CAN bus, you still need a way to tell that arduino to inject the message. If he wants to use the steering wheel button, he would still need to run wires from the steering wheel to the column.
	Appreciate 0 Quote

12-19-2016, 01:07 AM	#28
mkramer37 New Member 0 Rep 12 Posts Drives: 2011 328i xDrive Join Date: Aug 2016 Location: McLean, VA iTrader: (1)	The arduino would just passively receive messages, and would be located under the glove box. There are already wires connecting the buttons to the SZL, the car came with them already wired.
	Appreciate 0 Quote

12-19-2016, 01:11 AM	#29
matteblue3er Captain 243 Rep 949 Posts Drives: Racecar Join Date: Jul 2015 Location: Philly iTrader: (0)	Ahh I get what your saving. Have the arduino sniff the bus for the switch press
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12-19-2016, 09:26 AM	#30
dstrickland Banned 333 Rep 325 Posts Drives: BMW 06 325I Join Date: Mar 2016 Location: Atlanta, Ga, USA iTrader: (0)	I'm past how to activate the DS mode. I've wired it to the push function of the paddle. The issue at hand now is how to route the extra wire through the slip ring. I've searched for the slip ring, it seems the one they use for the digital performance steering wheel is suppose to have two 12 pin connectors in the back & an additional 3 pins in the front behind the airbag. When looking at the part number, it's the same one used on the e70 with heated steering wheel. But when I look at pictures of it on ecs or anywhere I can buy it, it has the extra 3 wires in front, but the back is still only 1-6pin & 1-12pin.
	Appreciate 2 Quote

12-19-2016, 01:56 PM	#32
mad1stgen Master Wagon Builder 481 Rep 911 Posts Drives: 2015 F wagon S55/6MT Join Date: Apr 2014 Location: Metro Detroit/Tampa Bay iTrader: (57)	Clock spring part number 61319169765 directly from my car with a heated wheel. It has an extra blue connector, with 4 wires, on the wheel side. and then ... http://www.e90post.com/forums/showth...=501185&page=2
	Appreciate 0 Quote

12-19-2016, 09:15 PM	#34
matteblue3er Captain 243 Rep 949 Posts Drives: Racecar Join Date: Jul 2015 Location: Philly iTrader: (0)	I'm not sure about this but is there more than one horn button? Maybe repurpose one
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12-19-2016, 10:10 PM	#37
dstrickland Banned 333 Rep 325 Posts Drives: BMW 06 325I Join Date: Mar 2016 Location: Atlanta, Ga, USA iTrader: (0)	I think I've found my solution, and it will free up 2 pins leaving me with an extra slot in case I want to do something else. I'm going to use only one stage of the dual stage airbag(if it wasn't safe, America wouldn't be the only country that uses them). If I wasn't the only driver of my car I would reconsider. The airbag takes a total of 4 pins on the wheel side & another 4 on the back side of the slip ring, one negative & one positive for each stage.
	Appreciate 1 Quote

12-20-2016, 08:21 PM	#40
dstrickland Banned 333 Rep 325 Posts Drives: BMW 06 325I Join Date: Mar 2016 Location: Atlanta, Ga, USA iTrader: (0)	Bmw definitely doesn't like people playing with the airbags. They did they're best to confuse the people working on them. Once pulling out the airbag, I took note that the stage 1 side was connected with yellow wires, one with brown stripe & the other with black stripe, the same with the stage 2 side except the wires were grey. Once I disconnected the grey pins to the stage 2 side, I pulled the connector on the rear side of the clock spring. Was happy for a second when I saw that everything was colored just like the steering wheel side. BMW's first switch up is that the black striped pins are actually the positive, the brown stripes are negative. The 2nd switch up is the stage 2 grey wires on the wheel side come out to the yellow wires on the backside, stage one's yellow wires come out to the grey side on the back. I pulled the grey wires out the back of the connector & plugged everything back in, then noticed I had codes for stage 1 & 2. Plugged the grey wires back in, stage 1 cleared. Then I pulled the yellow wires out the back & stage 1 stayed gone. Coded the airbag as a stage 1 only airbag & the lights gone. I now have 2 extra pins to connect to the slip ring, one goes to the the DS mode, the 2nd is yet to be determined. My ideal paddle retrofit is complete. I can activate sport, standard drive, upshift & downshift with the flick of a paddle.
	Appreciate 2 Quote