EDC and Servotronic stopped working

[Rajmun340]

I have a weird issue. My car is a factory bought bone stock ZCP, and at some point EDC modes and servotronic steering modes altoegether stopped working. With the exception of M engine power mode which still works. It does not matter if you use the center console button directly (for EDC, servo is only through idrive) or the idrive M-drive settings + steering wheel M button has no bearing whatsoever.

There was no warning messages (i do not have a code reader) but I remember how switching modes used to have a discernable effect (especially servotronic "Normal" and "Sport" steering modes).

What is puzzling is that all leds still turn on/off as they should except EDC and Servo do not work (I can feel that servo is always in sport no matter, EDC probably always sport mode )

I looked at the electrical system diagram from the aftersale doc (reproduced below) and I see there is a separate EDC-K module. If this has failed it would explain why EDC isn't working but the servo valve (numbered 1) is controlled directly by the DME (numbered 2), so that would point to a separate issue but they have both stopped working, I tend to think there is a common link , could it be in software ?

Could it be that when the EDC module fails, the DME automatically disables servotronic modes too ? Hopefully the right guy who knows those modules coding in and out can chime in.

I could simply go to the dealer and have them figure it out, but i'd rather know as much as possible about the issue first as it seems like a ticket for them to race my car all day long and i could not find anything on the forum through search.

[IIAp3x]

I had some issues with my EDC last year, and after several visits to the stealership I put coilovers on my car and coded out EDC..

One thing I know for sure is that if there is any fault with EDC it will default to sport mode- the stiffest setting... So unless it is in sport mode then the EDC module and system is working... Not sure about the servotronic though...

[Rajmun340]

Originally Posted by IIAp3x

I had some issues with my EDC last year, and after several visits to the stealership I put coilovers on my car and coded out EDC..

One thing I know for sure is that if there is any fault with EDC it will default to sport mode- the stiffest setting... So unless it is in sport mode then the EDC module and system is working... Not sure about the servotronic though...

That is good input, it confirms the harsh ride i've felt ever since. I wrote that wrong (corrected now), EDC stays in the stiffest mode no matter what is selected in my interface.

And my servotronic always feels in sport mode no matter what is selected. Can you check with your car if you feel the two servo modes or if it is always in sport too ? installing coilovers may not have fixed your servo if you have same issue.

[IIAp3x]

Originally Posted by JoeM3SSII

That is good input, it confirms the harsh ride i've felt ever since. I wrote that wrong (corrected now), EDC stays in the stiffest mode no matter what is selected in my interface.

And my servotronic always feels in sport mode no matter what is selected. Can you check with your car if you feel the two servo modes or if it is always in sport too ? installing coilovers may not have fixed your servo if you have same issue.

My issue was with EDC, as my servo works fine... I had a very minor leak in my right front strut which they finally figured out- but I still continue to have faults after I replaced it... I am much happier with a barebones set of coilovers now instead of the factory EDC...

You should be getting faults if it is defaulting to sport mode... That is weird that there are no faults...

[Rajmun340]

Originally Posted by IIAp3x

My issue was with EDC, as my servo works fine... I had a very minor leak in my right front strut which they finally figured out- but I still continue to have faults after I replaced it... I am much happier with a barebones set of coilovers now instead of the factory EDC...

You should be getting faults if it is defaulting to sport mode... That is weird that there are no faults...

i don't have an error code reader, but no fault/warning messages, also vehicle status shows all systems fine.

[Rajmun340]

Originally Posted by IIAp3x

I had a very minor leak in my right front strut which they finally figured out- but I still continue to have faults after I replaced it... I am much happier with a barebones set of coilovers now instead of the factory EDC...

You should be getting faults if it is defaulting to sport mode... That is weird that there are no faults...

I know you've said you servo works fine, but mine "works" too or i couldn't drive the car, it just is always in sport (behavior not the leds). I know i would never use normal servo mode anyway as it feels too loose but just for checking operation do you confirm both servo modes work ? sorry for being anal, just want to be sure.

[L4ces]

Perhaps something in this thread could prove insightful. Check wires etc...

http://www.m3post.com/forums/showthread.php?t=131953

[IIAp3x]

Originally Posted by JoeM3SSII

I know you've said you servo works fine, but mine "works" too or i couldn't drive the car, it just is always in sport (behavior not the leds). I know i would never use normal servo mode anyway as it feels too loose but just for checking operation do you confirm both servo modes work ? sorry for being anal, just want to be sure.

confirmed it this morning, both modes work... Can feel the difference starkly...

[JDM_CL9]

Possible that the steering angle sensor/ride height sensor got disconnected some how?

[Rajmun340]

Originally Posted by L4ces

Perhaps something in this thread could prove insightful. Check wires etc...
http://www.m3post.com/forums/showthread.php?t=131953

Thanks! I checked the front strut tower connectors they are well plugged. rear strut towers require removing rear seat rest, didn't do. Some people on that thread said they heard noise from a strut, i've been having a vague helicopter noise more like a repeat woosh sound. Don't know if that has anything to do with it. Again the car is in near pristine condition single owner never tracked.

Originally Posted by IIAp3x

confirmed it this morning, both modes work... Can feel the difference starkly...

Thanks for checking !!! I'm baffled why both my servo and edc are stuck in sport.

Originally Posted by JDM_CL9

Possible that the steering angle sensor/ride height sensor got disconnected some how?

isn't that inside the steering box ?

[Rajmun340]

I really appreciate how this forum can deliver when your turn comes. All the posts have been very helpful. I found the following old document on EDC III in the m5 board :

"Note: In case of a system failure where the system goes into a
firm setting, there is no visual warning to the driver of a
system problem. The only indication is that the ride is firm
at all times."

And

"If the medium solenoid valve circuit or control unit fails, the solenoids are de-energized which results in the firm setting." on page 7

The wording seems to say that if one of the sensors is defective (vertical, horizontal, angle..) you should get a warning. Since I got no idrive warning I must assume either the EDC-K module is toast or one strut has leaked. Preparing my car to go to the dealer (washing and detailing). Still no clue why the servo is always in sport.

EDC111.pdf

[Helmsman]

Joe, funny timing on this as just started to think my EDC seemed stiff all time. Tested the servo which seem fine going between normal/sport (only once up in speed the big difference occur really, always kept it in normal though).
Trying to work out the EDC changes I simply can't feel any differences anymore. Car only 27k on the clock and in mint cond so kinda surprise if they went south already. No obvious disconnect, engine bay always clean as a vissle.
No codes with Carly. Like you I hesitate going to the dealer as they tend to mess thing up....

Appreciate if you keep me posted after your dealer visit.

Thanks

[Rajmun340]

Originally Posted by Helmsman

Joe, funny timing on this as just started to think my EDC seemed stiff all time. Tested the servo which seem fine going between normal/sport (only once up in speed the big difference occur really, always kept it in normal though).
Trying to work out the EDC changes I simply can't feel any differences anymore. Car only 27k on the clock and in mint cond so kinda surprise if they went south already. No obvious disconnect, engine bay always clean as a vissle.
No codes with Carly. Like you I hesitate going to the dealer as they tend to mess thing up....

Appreciate if you keep me posted after your dealer visit.

Thanks

I'm astonished you get no codes. i don't have a reader. It is bad news when a system is designed with insufficient self-diagnosis. That gives no procedure for the dealer to follow they will poke around, possibly replace wrong parts, meanwhile increasing the risk of messing up.

That EDC note is unequivocal that if no visual warning was given then there is a system failure or solenoid valve failure. i interpret these as EDC-K module electronic has failed or the valve inside the strut or the strut has leaked. All other failures are related to sensors which should flag error codes.

I hate to bring my car to the dealer too, i have 17k miles.

i am guessing this is more widespread and many people are unaware of it as i was. if like me they programmed the m button to switch engine mode and EDC together, you feel that power surge and overlook the fact that EDC did not change.

[Helmsman]

Originally Posted by JoeM3SSII

I'm astonished you get no codes. i don't have a reader. It is bad news when a system is designed with insufficient redundant self-diagnosis. That gives no procedure for the dealer to follow they will poke around, possibly replace wrong parts, meanwhile increasing the risk of messing up.

That EDC note is unequivocal that if no visual warning was given then there is a system failure or solenoid valve failure. i interpret these as EDC-K module electronic has failed or the valve inside the strut or the strut has leaked. All other failures are related to sensors which should flag error codes.

I hate to bring my car to the dealer too, i have 17k miles.

i am guessing this is more widespread and many people are unaware of it as i was. if like me they programmed the m button to switch engine mode and EDC together, you feel that power surge and overlook the fact that EDC did not change.

Joe, had a good run today, the EDC's definitely doesn't change, chassie is bone hard. The servo is changing but the difference between the settings seem somewhat less than before, might be placebo.

Front connections seems fine, will have a go at the rear during the weekend.

Doesn't seem to be any fuses for the EDC which I find strange.

Totally agree on the lack of fault code. Will confuse the dealer, take time and potentially make them start dig in the wrong corner, bummer... However guess I'll have to contact them next week.

Cheers

[Rajmun340]

Originally Posted by Helmsman

Joe, had a good run today, the EDC's definitely doesn't change, chassie is bone hard. The servo is changing but the difference between the settings seem somewhat less than before, might be placebo.

Front connections seems fine, will have a go at the rear during the weekend.

Doesn't seem to be any fuses for the EDC which I find strange.

Totally agree on the lack of fault code. Will confuse the dealer, take time and potentially make them start dig in the wrong corner, bummer... However guess I'll have to contact them next week.

Cheers

Helmsman, diagrams above show no circuitry is shared between EDC and Servo, (except tapping to PT-can bus for connecting to DME). There is no good reason for both systems to go out at the same time. I wouldn't expect for you to have both issues too. My guess is that some electrostatic discharge could have zapped them both. The EDC-K box located in the trunk is probably insufficiently shielded in bmw's design. Static electricity will occur commonly when someone places luggage or clothings in the trunk (especially in winter) and charges will run straight through the least resistant path to ground which may well be through the EDC box and its tie to chassis ground. Having comfort access means those charges don't get a chance to discharge by touching the body of the car or a key lock.

Electronics they put in cars these day uses microchips that are extremely vulnerable to ESD and BMW does not go through sufficient efforts to shield those modules. If this was the electronic for an airborne system it would not even pass a first stage pre-design review visual inspection.

[BzsBimmer]

Are you guys using a generic reader or INPA? Most generic readers won't see these module errors and some of those errors may not show up in the form of a check engine or idrive error.

[Helmsman]

Originally Posted by BzsBimmer

Are you guys using a generic reader or INPA? Most generic readers won't see these module errors and some of those errors may not show up in the form of a check engine or idrive error.

I've checked with the Carly scanner. No codes.

Anyone who knows if a broken EDC module would generate code, I'm assuming it would?

[Rajmun340]

Only poor design for verification practices would not generate an automatic subsystem fail status. But there should be the possibility of active diagnosing the EDC-K from through PT-CAN from the DEM.

2. Monitor status
3. Actuate components
4. Test procedure
5. Special function
6. Test code

If the EDC-K ports are dead or hung it will respond to nothing and should fail all tests. the question is if EDC does not even have codes, do dealers need direct assistance from BMW gmbh to carry those tests. Will they even ask or will they try random things.

[Helmsman]

Joe,
took off and checked the front connectors today, also enjoyed myself (not) with ripping trunk trim. Tricky to get the module out at least on the E90 so simply did a visual check. Heard some had issues with moisture here however the area was all dry and nice.
Didn't touch rear connectors, after all should a damper be disconnected SURELY a code would be generated.

Tad irritating that systems on a well over $100k car start to mal function at 27k miles, oh well is what it is. Will call the dealer next week for a appointment ASAP, driving EDC daily in sport mode is bloody harsh!

Did you agree on a slot with your garage yet?

Edit: I noticed that module comes cheap from ebay - should my insurance not cover this. However I assume it would need to be a ZCP module, or do you know if the ZCP sw is located central..?

[Rajmun340]

Originally Posted by Helmsman

Joe,
took off and checked the front connectors today, also enjoyed myself (not) with ripping trunk trim. Tricky to get the module out at least on the E90 so simply did a visual check. Heard some had issues with moisture here however the area was all dry and nice.
Didn't touch rear connectors, after all should a damper be disconnected SURELY a code would be generated.

Tad irritating that systems on a well over $100k car start to mal function at 27k miles, oh well is what it is. Will call the dealer next week for a appointment ASAP, driving EDC daily in sport mode is bloody harsh!

Did you agree on a slot with your garage yet?

Edit: I noticed that module comes cheap from ebay - should my insurance not cover this. However I assume it would need to be a ZCP module, or do you know if the ZCP sw is located central..?

It seems you did not check the rear vertical acceleration sensors connectors, but i don't think that would be useful because sensor fault would already have given malfunction errors visual message.

I do not know if the code difference for zcp-EDC versus non-zcp-EDC is programmed directly into the EDC-K module or from the DEM. But it seems only 1 part serial number is available from realOEM.com

btw i estimate mine stopped working before 8,000 miles ! Due to lack of warning or error messages i didn't know it had stopped working.

should have dealer looking at it next week.

[Helmsman]

Originally Posted by JoeM3SSII

It seems you did not check the rear vertical acceleration sensors connectors, but i don't think that would be useful because sensor fault would already have given malfunction errors visual message.

I do not know if the code difference for zcp-EDC versus non-zcp-EDC is programmed directly into the EDC-K module or from the DEM. But it seems only 1 part serial number is available from realOEM.com

btw i estimate mine stopped working before 8,000 miles ! Due to lack of warning or error messages i didn't know it had stopped working.

should have dealer looking at it next week.

So been driving in sport mode for 9k miles? You better stop by a chiropractor while you're car is at the dealer!

[Rajmun340]

Originally Posted by Helmsman

So been driving in sport mode for 9k miles? You better stop by a chiropractor while you're car is at the dealer!

haha, it's not my daily it's a weekend garage queen. The roads are really good here and when i take it out i use all sport modes which is why i didn't notice. It's when some board members talked about how refined the m3 ride is that it got me wondering why my impression was nowhere close to 'refined' in default mode and I tried to feel the modes difference again and found none. I used to experiment with modes when the car was new and i remember it worked back then. Since servo doesn't work either the problem might be the steering angle sensor used by both edc and servo but why then is it not giving any malfunction or warning messages at all ?? If both EDC-K + steering sensor failed at < 8k miles that's disappointing at the least.