Andrew's S54 Swap

[FredK]

My guess I believe is the same as your guess--it's not going to limp, but it will store a code.

I guess for racers, not deleting DSC and the MK60 ABS is a good idea, because it's a pretty good 4 channel system. The E30 ABS system is antiquated! It's just a little more work, of course, to get it up and running--plumbing and wiring.

[SimplyDope]

Very nice!

[nando]

Well, onstalling the entire abs/dsc is possible, but in an e30 thats quite a bit of work.

Are you sure the dme cares about the clusters vin? In testing i havent seen any indication that it matters. You only get a tamper dot if you use the lightswitch too, which isnt neccesary in an e30.

Never been a member here but I read and research everywhere. I'm doing S54 + E36 M3 and 99% certain to use MSS54 DME without expensive send-it-to-Germany-and-pray EWS delete tuning.



This combination keeps non-limp DME and ABS:

• DME, EWS and key, and instrument cluster from same E46 M3
• EWS reader "ring" (normally mounted inside ignition cylinder) with key attached near or inside the "ring"
• late model (9/02 or later) MK60 DSC/ABS unit - its easy to tell early from late, the late ones are on the driver's side under the master cylinder
• two brake pressure sensors - threaded into the E46 M3 master cylinder, but who says they have to be? MITE46 (previously E30MIT) tee'd them into the lines from the master cylinder to the DSC/ABS unit
• DSC sensor - combined yaw gyro and lateral accelerometer - mounted under driver's seat in E46 (and its location IS critical)
• This setup is used in a C Mod car which has been racing for four years.

If you install it like this (with no steering angle sensor) none of the DSC/traction control features work but the full 4 channel ABS works normally. If you install the steering angle sensor and wire a DSC pushbutton to the MK60 unit you can have fully functional E46 M3 DSC and ABS - but I don't know about you, I really don't want to have to turn off DSC every time...

(I cannot promise that the early MK20 DSC/ABS unit will or won't work - but I do know that the later MK60 unit will. The early MK20 unit will use standard E30/E36 wheel speed sensors, but requires that you obtain, mount, and wire a "precharge pump". The late MK60 unit requires no additional pump, but does require E46 wheel speed sensors).



Not installing the (or installing a faulty/broken) steering angle sensor gives two idiot lights and no DSC/traction control features, but retains full ABS function. Sounds like the easiest way to do it, unless having factory functionality of your dashboard "Brake" idiot light is important to you. (The second idiot light is the DSC one, which wouldn't really apply at that point).

[nucci]

Are you sure the dme cares about the clusters vin? In testing i havent seen any indication that it matters. You only get a tamper dot if you use the lightswitch too, which isnt neccesary in an e30.

To be honest I'm not quite sure why the cluster is required. I don't think it has anything to do with the VIN. I *think* it has something to do with completing the EWS system. When I can figure it out conclusively I'll report back.

[gobuffs]

Installing E46 ABS to an E30 isn't that hard. Should have mine up and running in a couple weeks.

The ECU needs to see the speed signal from the diff, however the ECU doesn't massage the signal enough tomake a big enough difference- you can wire the speed signal from the diff to the ECU.

[nucci]

The ECU needs to see the speed signal from the diff, however the ECU doesn't massage the signal enough tomake a big enough difference- you can wire the speed signal from the diff to the ECU.

Can you explain in more detail? E46 M3 has no diff speed sensor or trigger wheel. Its speedometer reading comes from some level of processing added to the left rear ABS sensor - which is a 48 tooth wheel. Classic 188mm diffs have a 9 tooth wheel. I like the direction you're going, but need to understand it further.

edit - I looked back through some documents since you piqued my interest. It is clear by reading a list of MSS54 DME specific error codes that "speed sensor" is an input for the DME (and BMW does have a legacy of doing this). It is also clear that the input "F_DFAHL" comes from the instrument cluster, and that is the conditioned left rear wheel speed sensor - which we have known for a long time is the one which drives the speedometer and cruise control. I'm going to look at it more tomorrow.

[Roysneon]

I love all you guys for having this discussion so I can steal your knowledge.

[Wanganstyle]

Can you explain in more detail? E46 M3 has no diff speed sensor or trigger wheel. Its speedometer reading comes from some level of processing added to the left rear ABS sensor - which is a 48 tooth wheel. Classic 188mm diffs have a 9 tooth wheel. I like the direction you're going, but need to understand it further.

edit - I looked back through some documents since you piqued my interest. It is clear by reading a list of MSS54 DME specific error codes that "speed sensor" is an input for the DME (and BMW does have a legacy of doing this). It is also clear that the input "F_DFAHL" comes from the instrument cluster, and that is the conditioned left rear wheel speed sensor - which we have known for a long time is the one which drives the speedometer and cruise control. I'm going to look at it more tomorrow.

do you have any experience with fitting the OEM MSS54 DME and removing the ABS? Or are all the e46M track guys afraid of loosing the ABS/DSC? its not that scary to track battle on slicks with no abs; just have to be used to it! To some its more thrilling to battle wheel to wheel with zero drivers aids.

Fear of flat spotting is one of the things that makes tracking exciting, just like fear of loosing money when you go to a casino and gamble with real money. Modulate yourself!!!

i.e:

Mss54+ all ews stuff and cluster if needed

speeds sensor trigger from left axel

nothing else? no dsc, no ABS, no other Bs??


***
e46M ABS does come in a few flavors, I would prefer to wait out for the later versions (from usa 2005/06 M3 with CSL spec 345mm big front rotors and CSL increased diameter rear pistons+ motorsports flash before installing it in place of my non-abs.

also, if going on bandwagon for electronic speed assists why not just run a DTA standalone + program in full traction control from the DME ?

[nando]

Can you explain in more detail? E46 M3 has no diff speed sensor or trigger wheel. Its speedometer reading comes from some level of processing added to the left rear ABS sensor - which is a 48 tooth wheel. Classic 188mm diffs have a 9 tooth wheel. I like the direction you're going, but need to understand it further.

edit - I looked back through some documents since you piqued my interest. It is clear by reading a list of MSS54 DME specific error codes that "speed sensor" is an input for the DME (and BMW does have a legacy of doing this). It is also clear that the input "F_DFAHL" comes from the instrument cluster, and that is the conditioned left rear wheel speed sensor - which we have known for a long time is the one which drives the speedometer and cruise control. I'm going to look at it more tomorrow.

the speed signal triggers from the rear left axle (ABS/DSC system), but that's not the signal the DME or cluster sees. As stated, the ABS wheel has 48 teeth. Traditionally BMW has used 9 pulses per rotation for a VSS. The signal that the cluster and DME get is actually a conditioned VSS from the DSC system, it's not reading straight from the ABS sensor - as far as I can tell from testing the E46 M3 cluster & dme, the conditioned signal is also 9 pulses per rotation. This is based off the K factors (pulses per mile/km) inside the speedometer and my own calculations. Otherwise, you couldn't use MSS54 with an E30 or E36 diff-mounted 9 tooth speed sensor, which I'm pretty certain has been done many times.

basically what I'm saying is, unless you are using the entire abs/DSC system, there's no point in worrying about the left/rear ABS wheel signal, because you'd be using the 9-tooth diff sensor anyway.

[nucci]

You bring good information.

If you look at how things are connected up in the native E46M3 wiring, all four ABS sensors connect directly to the MK60 DSC, which outputs F_DFAHL to the cluster, which then outputs it to the DME. I don't see any direct connections of F_DFAHL into the DME - it goes through the cluster. If they did devote processing and wires to this F_DFAHL channel, I cannot imagine that this signal is also available on the CAN bus. If it was there wouldn't need to be wiring from the MK60 DSC to the cluster in the first place, right? Hence deleting the cluster without making other measures to satisfy the DME F_DFAHL input would result in the DME not knowing the car's road speed, which does have at least 2 error codes.

as far as I can tell from testing the E46 M3 cluster & dme, the conditioned signal is also 9 pulses per rotation.

How did you test it?

Otherwise, you couldn't use MSS54 with an E30 or E36 diff-mounted 9 tooth speed sensor, which I'm pretty certain has been done many times.

I didn't know this - are there places to read about it?

I figure the people likely to do this swap DIY style are probably E30 or E36 owners, and so I'm trying to figure out whether there are more benefits to keeping the E46 M3 cluster and integrating the gauge movements/circuit board into an earlier dash housing, or figuring out how to run without the E46 M3 cluster and still keep the DME and EWS satisfied.

If the E46 M3 cluster is kept, I would imagine that most swappers would like their odometer to retain the chassis' original mileage, and most E46's getting parted out have from 40K to 100K. Many E30 and E36 chassis have 3-5x that many miles. In order to "add" miles to one of these clusters with hobbyist-level programmers, you need to disassemble the cluster, de-solder the M35080 chip, read the raw dump and save it, create a new file for the M35080 which retains the VIN but has your new desired mileage and a corrected checksum, resolder the chip and reassemble the cluster, erase some/all of the code on the chip in the EWS box (still not clear on this) and reset its mileage to 316km, and then you can plug all these parts into the car and go. If done correctly the EWS will then update its mileage from the cluster when everything is powered up. If you are keeping the LCM you will need to change the mileage there too, but you can do that with inexpensive diagnostic tools.

If this can be done without that cluster and all its drama, it might be a better option for some. However, I am not sure if you will have cruise control . The MFL buttons on the right side of the steering wheel are connected on K-Bus to the cluster, and with one wire, "FGRS" signal multifunction steering wheel, to the DME. I don't know if only the DME wire is important, or if the cluster takes the K-Bus input and makes CAN outputs to the DME.

[nando]

You bring good information.

If you look at how things are connected up in the native E46M3 wiring, all four ABS sensors connect directly to the MK60 DSC, which outputs F_DFAHL to the cluster, which then outputs it to the DME. I don't see any direct connections of F_DFAHL into the DME - it goes through the cluster. If they did devote processing and wires to this F_DFAHL channel, I cannot imagine that this signal is also available on the CAN bus. If it was there wouldn't need to be wiring from the MK60 DSC to the cluster in the first place, right? Hence deleting the cluster without making other measures to satisfy the DME F_DFAHL input would result in the DME not knowing the car's road speed, which does have at least 2 error codes.

this is really simple - you'd just run the VSS signal from an E36 or E30 cluster to the DME. since it all seems to be based off a 9 pulse per rotation signal, it doesn't matter what cluster it came from. the signal on the E30 is definitely cruder, but for what the DME uses it for, it doesn't really make much difference.

How did you test it?

on my workbench. :)

I didn't know this - are there places to read about it?

I'd just ask anyone who's already done this swap in an E30. There are lots using stock DME's and E30 clusters (usually from an M3). they surely must be using the E30's VSS signal, which is the same on an E36.

I figure the people likely to do this swap DIY style are probably E30 or E36 owners, and so I'm trying to figure out whether there are more benefits to keeping the E46 M3 cluster and integrating the gauge movements/circuit board into an earlier dash housing, or figuring out how to run without the E46 M3 cluster and still keep the DME and EWS satisfied.

I don't think EWS communicates with the cluster. Really, all the DME gets from the cluster is the road speed signal, but it's just a dumb raw signal on it's own wire. the CAN signals seem to be pretty much related to driving the gauges and maybe updating the mileage reading, but if you're isolating it outside of the E46 I don't see how it makes any difference. Neither of my DMEs have complained that the cluster's VIN doesn't match, but I haven't tried it with EWS hooked up yet.

If the E46 M3 cluster is kept, I would imagine that most swappers would like their odometer to retain the chassis' original mileage, and most E46's getting parted out have from 40K to 100K. Many E30 and E36 chassis have 3-5x that many miles. In order to "add" miles to one of these clusters with hobbyist-level programmers, you need to disassemble the cluster, de-solder the M35080 chip, read the raw dump and save it, create a new file for the M35080 which retains the VIN but has your new desired mileage and a corrected checksum, resolder the chip and reassemble the cluster, erase some/all of the code on the chip in the EWS box (still not clear on this) and reset its mileage to 316km, and then you can plug all these parts into the car and go. If done correctly the EWS will then update its mileage from the cluster when everything is powered up. If you are keeping the LCM you will need to change the mileage there too, but you can do that with inexpensive diagnostic tools.

It should be way easier on the E36, many things are much more similar than they are on the E30. like the fuel level sensors.. but, I think keeping the M3 cluster is worthwhile for a number of reasons. They're dirt cheap for one - price one out vs a mint E30 M3 cluster sometime. :)

I can't see any benefit to keeping the E46 LCM though, it will cause way more headaches, especially if VIN's don't match. You have to do some mods to the cluster for the indicator lights to work but it's not that big of a deal, and it frees you up to use the extra spaces for more useful purposes. like a wideband and oil pressure gauge. :D

If this can be done without that cluster and all its drama, it might be a better option for some. However, I don't think you will have cruise control unless somebody can interpret the CAN signals created by the MFL steering wheel buttons. The buttons on the right side of the steering wheel supply commands on the K-Bus to the cluster, which turns them into CAN commands and sends them to the DME.

if you don't use the LCM, the cluster doesn't really add a lot of drama - it really is just a display device when you run it stand-alone. If your transplant car has higher mileage than the cluster, you can basically run the odometer on a bench setup to get it to your desired mileage. certainly easier than removing the chip and all that. how long would it take to add 100,000 miles at 180mph? :p

although, there is an issue with recoding the K-factor without changing the odometer's checksum. basically, you're stuck with the K-factor's built in to the cluster for the odometer, even though you can code new ones, it will throw a checksum error because I believe the E46 cluster stores pulses, not kms or miles. You can change the speedometer to whatever you wish, which is nice. fortunately, the built in odometer K-factors are extremely close to what I'd need, close enough that messing with the odometer reading and checksum isn't worth it. And there are two to choose from which at least gives a little bit of wiggle room.

what I really want to find out is, what does the DME actually do without the DSC/ABS system & emissions junk? if it's just going to throw an error light - who gives a shit? at the price people are charging for flashes, it hardly seems worth the trouble. I'll find out eventually but I need to finish other things first. :)

[nucci]

this is really simple - you'd just run the VSS signal from an E36 or E30 cluster to the DME. since it all seems to be based off a 9 pulse per rotation signal, it doesn't matter what cluster it came from. the signal on the E30 is definitely cruder, but for what the DME uses it for, it doesn't really make much difference.

That was exactly what I was gathering.

if you don't use the LCM, the cluster doesn't really add a lot of drama - it really is just a display device when you run it stand-alone. If your transplant car has higher mileage than the cluster, you can basically run the odometer on a bench setup to get it to your desired mileage. certainly easier than removing the chip and all that. how long would it take to add 100,000 miles at 180mph? :p

Math it out - a little over 23 days!

although, there is an issue with recoding the K-factor without changing the odometer's checksum. basically, you're stuck with the K-factor's built in to the cluster for the odometer, even though you can code new ones, it will throw a checksum error because I believe the E46 cluster stores pulses, not kms or miles. You can change the speedometer to whatever you wish, which is nice. fortunately, the built in odometer K-factors are extremely close to what I'd need, close enough that messing with the odometer reading and checksum isn't worth it. And there are two to choose from which at least gives a little bit of wiggle room.

Cluster stores miles - I've got a couple of late E46 M35080 (odo chip) dumps. The first 16 8bit addresses are all summed up and that is the mileage. If you are talking about the same K-factor that I've read about, your only two options are equivalent to a rear tire of about 25.7" diameter, and one a tiny bit shorter. I'm running 245/40-17 at about 24.7" so it is not even close. I cannot imagine you've got 25.7" diameter tires tucked in an E30, do you?

what I really want to find out is, what does the DME actually do without the DSC/ABS system & emissions junk? if it's just going to throw an error light - who gives a shit? at the price people are charging for flashes, it hardly seems worth the trouble. I'll find out eventually but I need to finish other things first. :)

99% certain that the DSC tells the DME to use torque reduction strategies when it has certain error situations - what those are, I guess we will find out.

[nando]

I dunno - using 9 pulses per rotation, the K factors in the cluster were well under 1% off my E30's tire size (235/50-15). they are stored in KMs, I think it was only 10 or maybe 20 pulses off an entire mile? out of ~7500 or somewhere in that ballpark.

the reason I believe you cannot change the odometer's K-factor without getting a checksum error is because it compares the calculated mileage vs the stored mileage (pulses vs miles or KM). I think you'd have to zero out the odometer, change the K factor, and then change the odometer back up to what you wanted it to read. but, that's just a guess of what I've tried. maybe somebody else has modified the odometer's K-factor. I know for certain you can use whatever you want for the speedo..

a simpler way would be to intercept the signal and modify it a bit..

[nucci]

I dunno - using 9 pulses per rotation, the K factors in the cluster were well under 1% off my E30's tire size (235/50-15). they are stored in KMs, I think it was only 10 or maybe 20 pulses off an entire mile? out of ~7500 or somewhere in that ballpark.

the reason I believe you cannot change the odometer's K-factor without getting a checksum error is because it compares the calculated mileage vs the stored mileage (pulses vs miles or KM). I think you'd have to zero out the odometer, change the K factor, and then change the odometer back up to what you wanted it to read. but, that's just a guess of what I've tried. maybe somebody else has modified the odometer's K-factor. I know for certain you can use whatever you want for the speedo..

Good stuff worth reading here.

Matt

[nando]

good read, I've been talking to that guy so maybe I'll pick his brain a bit.

one possiblity is that the E46 does in fact use 10 pulses per rotation, and if that's true, I believe it works in our favor. I'll have to do the math to see how a 9 pulse signal works on a K-factor based on a 10 pulse signal.

anyway, getting the speedo accurate was never the issue to me, you can adjust the displayed MPH to your hearts content - getting an accurate odometer will be much harder.