25 replies to this topic

[meb58]

A wheel speed sensor was not installed properly and came into contact with the crankshaft pulley. The pulley wore away the insulation exposing the copper wire causing a short or fault between the DME and DSC. I assume DME means digital motor electronics...

Could such a short cause damge to the DME? No speedo, no odometer, no trip odometer, no ABS (nice!) no traction control, intermittent gas guage...

I followed the line from the wheel speed sensor and it ends at what I think is the DME...a sizable electronic box attached to a hydraulic valve with four lines running under the car...

I reinstalled a new wheel speed sensor, disconnected the battery - hoping this would re-set the system - but alas, all is the same.

I love mechanical linkages! When they break they are usually very apparent!

[gruntguru]

A wheel speed sensor was not installed properly and came into contact with the crankshaft pulley. The pulley wore away the insulation exposing the copper wire causing a short or fault between the DME and DSC. I assume DME means digital motor electronics...

Could such a short cause damage to the DME?

That would be unusual. Wheel speed sensors are usually inductive (2 wires, unpowered) and a short to ground is usually harmless. If it is Hall effect (3 wires) a short to ground is more likely to do damage. Unfortunately your symptoms and procedure are suggesting consequential damage. Is the DME getting power? Check fuses.

[McGuire]

Let's bqck up and start at the beginning:

1. Year, make, model, relevant equipment, modifications if any

2. Operating symptoms

3. Malfunction indicators illuminated

4. Diagnostic trouble codes

[OfficeLinebacker]

1) The crankshaft pulley is that close to a wheel speed sensor? Or is it a crank angle sensor or smth?

2) DME....is that a Porsche system?

[meb58]

McGuire,

I have to dig up the codes

2005 Mini JCW Mini cooper, Xenon lights, heated seats and Harmon Kardon...these are the only options outside the JCW package

No engine mods...and the engine still runs quite strong at 171,000 miles

Maulfunction indicators; check engine light, ABS, E-Brake light, Low psi tire warning light, Traction control light...none of the electronic trip information works; real time fuel mileage, avg fuel mileage, miles traveled etc.

Operating symptoms...not sure what you mean but the car drives quite well except there is no ABS or Traction Control - the only two operational failures

OfficeLinbacker,

DME is a Porsche system, but that's all I know about it. The general diagnostics from BMW was that the problem "...is between the DME and the DSC."

I can acutally live with all of the lights and the lack of ABS and Traction control. But the car is registered in Connecticut, USA and the check engine light means an automatic emmisions failure...I have about 55 days to remedy or the car must be removed from the road...or registered in New York

Thanks for your help!!! Would a photo of what appears to be the DME be helpful?

[Canuck]

DME is typically the engine/trans control along with your dash etc. The DSC is, if I'm not mistaken, your traction control.

DME is typical for BMW (and the new Mini) and Porsche or perhaps Bosche in general.

[cheapracer]

A and the check engine light means an automatic emmisions failure...I have about 55 days to remedy or the car must be removed from the road...

Well if time gets away from you I'm sure theres either a wire to be cut or an LED to be removed?

I'm no electronics expert by any stretch so I had a moment and asked My friend Gary Oogle and he mentioned these to me..

http://www.google.co...M...mp;oq=&aqi=

http://www.northamer...e-pressure.html

[McGuire]

McGuire,

I have to dig up the codes

2005 Mini JCW Mini cooper, Xenon lights, heated seats and Harmon Kardon...these are the only options outside the JCW package

No engine mods...and the engine still runs quite strong at 171,000 miles

Maulfunction indicators; check engine light, ABS, E-Brake light, Low psi tire warning light, Traction control light...none of the electronic trip information works; real time fuel mileage, avg fuel mileage, miles traveled etc.

Operating symptoms...not sure what you mean but the car drives quite well except there is no ABS or Traction Control - the only two operational failures

We need to record the codes and review the data or none of us has any idea what we are talking about. We are just throwing out suggestions. But as long as we are, good chance there is nothing wrong with the DME -- the CE lamp might simply be no data to DME from ABS/DSC. First, check ALL the fuses. Could be the DSC is simply not powering up.

If the fuses are ok, unplug and re-plug the DSC and ensure the connector is clean and secure. If you have been living clean maybe you will get lucky.

[Fat Boy]

It sounds to me like there has been a CAN bus failure somewhere. If the speed sensor was an 'active' (i.e. powered / 3-wire) sensor, it may have had the same power source as the CAN link itself. When it went, it's feasible that it took the power to the whole system with it, although, I have to say I've never seen it happen quite like that. The sensor regulated power is short protected and shouldn't die that easily. It's possible that there is still a short somewhere in the system that is killing the CAN link and that's why nothing works. Either way, making sure the CAN is alive would be where I'd start my search.

[meb58]

McGuire, I will get the codes by tomorrow. I understand the difficulty.

Fat Boy, what is a can? I fully expect a few comical replys...

Cheapracer, I am in the same boat, I know nothing about car electronics, but I'll give those links a look.

[McGuire]

It sounds to me like there has been a CAN bus failure somewhere. If the speed sensor was an 'active' (i.e. powered / 3-wire) sensor, it may have had the same power source as the CAN link itself. When it went, it's feasible that it took the power to the whole system with it, although, I have to say I've never seen it happen quite like that. The sensor regulated power is short protected and shouldn't die that easily. It's possible that there is still a short somewhere in the system that is killing the CAN link and that's why nothing works. Either way, making sure the CAN is alive would be where I'd start my search.

That's sorta what I'm thinking. Either the DSC is not powering up or is damaged and pulling down the CAN bus -- the failures are all up and down the CAN bus, cluster, A/C, all the MILs, etc, but pointing at the DSC. I have no idea what kind of fault protection the DSC employs, so it's possible a shorted WS sensor a) could take out the DSC or b) maybe just popped the fuse. Without plugging in we are just guessing tho.

[meb58]

I forgot to add that all the fuses are fine - I checked these after this happened...unless there are other fuses in line or in the DME or DSC??? This probelm began as an intermittent one...

By the way, this car has ASC and not DSC...the first being traction control and the second I think is a yaw type control. ASC can be switched on and off but DSC cannot - from what i am told.

The question here is why is there a fault between DME and DSC if the car has no DSC option? Possibly a different achronym?

Edited by meb58, 10 September 2009 - 17:48.

[McGuire]

Fat Boy, what is a can? I fully expect a few comical replys...

CAN stands for Controller Area Network. The CAN bus is a circuit on which all the little black boxes (nodes) on your car communicate with each other, and which technicians can also use to monitor and troubleshoot all of it. Nodes generally include the engine ECU, ABS and/or ESC controller, instrument cluster, etc, each with its own address. For example, the engine ECU will place data on the line which the instrument cluster uses for gauge values, MILs, etc. On your OBD (On-Board Diagnostics) connector, pin 6 (high) and pin 14 (low). With the ignition off there should be 60 ohms across those two terminals. That tells you only that the circuit is physically present and intact, not that it works.

[Fat Boy]

CAN stands for Controller Area Network. The CAN bus is a circuit on which all the little black boxes (nodes) on your car communicate with each other, and which technicians can also use to monitor and troubleshoot all of it. Nodes generally include the engine ECU, ABS and/or ESC controller, instrument cluster, etc, each with its own address. For example, the engine ECU will place data on the line which the instrument cluster uses for gauge values, MILs, etc. On your OBD (On-Board Diagnostics) connector, pin 6 (high) and pin 14 (low). With the ignition off there should be 60 ohms across those two terminals. That tells you only that the circuit is physically present and intact, not that it works.

That's pretty much it. You need to make sure there isn't some sort of short to ground on either end of it. A CAN node needs to have power as well, so make sure that there is a controlled voltage source that is working as well.

[McGuire]

If I may clarify/amplify, the only voltage you should see on the CAN lines is the signal output of the nodes. So with a digital voltmeter from each CAN line to ground, you should see 1.5v to 3.5v, rapidly fluctuating. Additionally, there is a 120 ohm termination resistor at each end of the wires, so if you connect an ohmmeter across the lines (powered down) you will see 60 ohms. And obviously, if there is a short to ground on either line it will pull the circuit low, the CAN bus won't work and you won't see any signal on the line. To diagnose the signal beyond that you will need a scope, and to read the data encapsulated in these physical layer signals you will need a dedicated interpreter or an adapter (serial or USB) and software with a PC. Adapters are available with either standard 9-pin sub-d connector or OBD II interface.

...if anyone is interested, the CAN bus was originally developed in the '80s by Bosch as an automotive communications network stanadard but has since expanded elsewhere. CAN is a two-wire serial differential bus that may employ a shielded or non-shielded twisted pair, a ribbon cable or conventional harness. Each node incorporates its own CAN transciever and controller with two wiring connections into the network, CAN high and CAN low. However, there are more than a dozen various serial communications systems used in the industry and it is not at all uncommon for vehicles to employ mutiple networks connecting dozens of nodes, from engine control to ABS to audio systems. With this capability they can do stuff like couple stereo volume to vehicle speed, notify OnStar of an airbag deployment to alert authorities, and integrate functions like electronic throttle management with traction or stability control.

[meb58]

I finally took the time to trace the problem from the source - the unintentional ground - to where all the wires terminate.

Unfortunately for me the Hydro Unit ASC connections burned up. The two components required to repair this cost $3,023.00 without tax and without labor...I cannot stop wondering why there is no fuse box in-line.

I may go hunting in a junk yard...I'm not too keen to use a used part since it controls so many things...I may be better off just leaving this alone.

As a reminder - no ABS, no Traction control, no gas guage, no speedometer, no low tire psi warning...the gas guage and speedo are most important but I've already worked around those. And hopefully most of us drive by the tach anyway...I'll superimpose speedometer readings on the tach and I'm set. Traction control and ABS are a pain in the back side on the track anyway. I just talked myself into saving $3,000.00!!!

Edited by meb58, 03 November 2009 - 19:25.

[saudoso]

The junk yard deserves a visit, that's the kind of stuff that survives a total. Unless it caused it.

[meb58]

Your two sentenses are actually very funny..dry but funny.

Click on the link below to see the burn socket or plug...the corresponding tabs on the hydro unit are alos burned. I can replace the hydro unit but the socket/plug contains all the wires that feed info to the dash...I do not think these feed any performance data to the systems operating the car; abs traction control etc???

http://i37.tinypic.com/1040y6s.jpg

The junk yard deserves a visit, that's the kind of stuff that survives a total. Unless it caused it.

Edited by meb58, 04 November 2009 - 16:20.

[saudoso]

I'm such a smart ass...

*DISCLAIMER* I'm not in the business of fixing cars, I deal with computers and rapid prototyping equipment.... but I am used to the smell of carbonized wiring

That said, that thing looks well burnt, and I would guess most of the problems come from the failing wiring, not the hydro unit. ABS/TC only would fail from the unit right? What else goes on there?

I really don't know this stuff to say something really useful, but I'd try to figure out what is connected to that interface and how it relates with what you see failing. It could be just that many systems are connected thru that interface and it is not forwarding data. Or could be that it shorted really bad and burnt stuff all around. An schematics for the interface and a multimeter could get you closer to the answer.

BTW, did you plug a diagnostic system to the car and see what it reports?

Edited by saudoso, 04 November 2009 - 21:16.

[meb58]

I don't own a diagnostic tool...a series of codes that relate to all the systems not working came up when I brought the car in for a look see. But the codes are a secret...no one will let me have them.

[saudoso]

If you go to a shop and ask for a cost estimate on fixing it won't they tell you what is wrong?

[meb58]

They showed me all the codes and I read the print out carefully. They simply stated it could cost between $70.00 and $3,000.00 to find the problem...this does not inlcude fixing it. So I used some logic based upon a shorted wheel speed sensor and traced the wire back to the Hydro Unit ASC. At this point a diagnostics is probably best simply to determine what is burned and what is not. I have no problem with that path.

I inlcuded the photo for those who were trying to help...and frankly I learn a lot more when I ask for help and try to fix on my own. But I think I have gone as far as I can based simply on the fact that I dod not own the proper diagnostic tools. I could assume everything is burned and replace it all....na!

[saudoso]

They showed me all the codes and I read the print out carefully. They simply stated it could cost between $70.00 and $3,000.00 to find the problem...this does not inlcude fixing it. So I used some logic based upon a shorted wheel speed sensor and traced the wire back to the Hydro Unit ASC. At this point a diagnostics is probably best simply to determine what is burned and what is not. I have no problem with that path.

I inlcuded the photo for those who were trying to help...and frankly I learn a lot more when I ask for help and try to fix on my own. But I think I have gone as far as I can based simply on the fact that I dod not own the proper diagnostic tools. I could assume everything is burned and replace it all....na!

How deep does the wiring from that interface goes? What else was connected there?

Do you think you can repalce it? If yes, try to get one and do it. It will make things easier and it has to be replaced anyway.

[McGuire]

First, inspect and repair all the wires and terminals on the connector, then test each one for continuity, zero ohms from terminal to terminal on each wire. Also test for power and grounds on the appropriate wires, referring to the relevant wiring diagram in the service manual. Once you have all that squared away, plug the connector into the box and see if it works. If not, replace the box. Since you don't have data diagnosis equipment you are flying on visual, so you will have to rely on your eyes and DVOM to identify any problems.

[mariner]

I think you said you were located in Connecticut. If so you should have an Autozone near you. Autozone carry OBD11 readers and will try to pull the fault codes for free.

It could be that being BMW they tie all the codes up and don't use a std interface but IN THEORY all US sold cars should "have the std. OBD11 connection within 12" of the steering wheel and accesible without tools" if I can remember the legistaltion correctly. The standard OBD11 codes are supposed to be readable but BMW probably have another level which requires a full diagnostic link which can exercise the systems. Nonetheless faced with such useful customer advice as $70 to $3,000 there should be an alternative route to the BMW dealer somewhere near you.

[meb58]

Thank you McGurie...I amy give it a shot. Also, apparently once the hydro unit is replaced it will work only after BMW "initializes" the system again??? - a $112.00 fee, not a big deal but a hassel.


mariner, I am told that BMW indeed use another level of OBDII. The tool is special...

I know I must appear a little apprehensive