BMW guys: Help me understand these fault codes and their causes (09 E82 128i)

SES popped on solid on my drive home. Joy. Pulled the codes: got two active, plus several more stored. The active are:

A0B5 CAS: Fault road speed signal
2C2D DME: Oxygen sensor before catalytic converter: coasting mode check

The stored codes are:

2DEB DME: Power management vehicle electrical system
2C3D DMW: Oxygen sensor before catalytic converter: line fault
+ 2 ABS codes for the front left and right wheel speed sensors

I have had no previous SES lights in recent memory. I did have the ABS light come on a few times for wheel speed sensors, but all four have been replaced within the last year or two; the ABS light is not on now.

The oxygen sensor codes seem to suggest the sensor is on its way out - not surprising at 137k miles - but I don't know much about the exact faults, so clarification would help before I start ordering parts (or possibly checking with the dealership, as I'm still under the extended SULEV warranty). I'm at a loss as to what's causing the CAS fault and the 2DEB power management fault. On the subject of the latter, however, I looked quickly at the live data and saw the battery voltage was 15v, which seems very high to me, but I know these cars have a fairly complex charging system, so any clarification of what the proper operating voltage should be would be helpful. Finally, is there anything in the live data or active test regime that I could use to pin down what's going on?

Oh, and really finally, I'm still chasing down an increasingly severe vibration from what seems likely to be the driveline - any chance any of these could be influenced by vibrations through the chassis? Seems unlikely to me, but I figured I'd mention it.

No offense but what are you using to scan for these codes as they look (and google) like strange code numbering systems.

It's a BMW-specific scanner (Foxwell 510 (I think) with BMW software). These are typical BMW fault code formats.

Left out the last 3 alpha characters and got better results. The road speed sensor error could be a calibration issue caused by a previous wheel spin. Clear those ABS codes and rescan after a few weeks to see if anything is pending/stored. 

The 2C2D code obviously points to the oxygen sensor (pre-cat) along with the 2C3D code. These could be caused by faulty O2 sensors (most likely culprit if they are original) OR be caused by a misfire condition which may also explain the vibrations (less likely with no misfire codes). Also check the wiring harness from the sensor to the main harness to make sure it didnt rub against the headers or get frayed by the firewall. 

I would clear codes and see what comes back in the next few weeks. If O2 sensor codes persist without misfire codes and they are original I would replace the pre-cat O2 sensors with Bosch direct fit replacements from somewhere like rockauto.

02Pilot said:

Oh, and really finally, I'm still chasing down an increasingly severe vibration from what seems likely to be the driveline - any chance any of these could be influenced by vibrations through the chassis? Seems unlikely to me, but I figured I'd mention it.

Not sure on the fault codes, seems plausible that the charging system has an issue though.  Could also be a bad battery though, I know that all kinds of wonky stuff happens when the batteries fail on a BMW.  If I recall correctly, the car increases the charging voltage of the battery as the battery ages to compensate, it seems like you could get a fault if the car has to work too hard to charge the battery.  

For the vibration, the dual mass flywheels in the manual E9x cars are known to slowly leak grease until they fly apart.  You should be able to peek in your bellhousing and if its full of grease, your DMF is cooked.  Driveline vibrations are the main symptom, but they're a main symptom of a lot of issues related to the driveline--worn flex disc, CSB, CV axles.  My 2006 E90 had a vibration on acceleration that I couldn't track down and since it was my only vehicle at the time I couldn't just take it apart to figure it out so I ditched it without finding the problem--I always wanted to know what caused it but the next owner, who was a BMW tech, wouldn't answer me after I asked him about it a couple months later.  

In reply to rothwem :

If it's the flywheel, though, why would it be more sensitive to road speed than engine speed? I'm not saying it's not a possibility (one I do not particularly want to deal with), but it seems less likely in this case.

In reply to Olemiss540 :

The only reason I didn't clear the codes is because I'm debating whether to take it to the dealership since it's still under the 15/150k SULEV warranty, which should cover the O2 sensors. I suppose they'll likely come back anyway, so it shouldn't make much difference. Hadn't thought of wheel-spinning setting a fault, but it makes sense, as the snow tires are much more likely to lose traction than the summers, even when not driving terribly hard.

02Pilot said:

In reply to rothwem :

If it's the flywheel, though, why would it be more sensitive to road speed than engine speed? I'm not saying it's not a possibility (one I do not particularly want to deal with), but it seems less likely in this case.

Crap, yeah, I'm a dummy.  I kinda think of the flywheel as a part of the driveline because its after the engine and before the wheels, even though it spins at the same speed as the motor, so it would be more likely to have vibrations that correspond to engine speed, not road speed. 

Anyways, I don't think the driveline stuff has anything to do with your codes.  

I'm guessing you've already thought about this more carefully than my quick reaction, but if the dealer's going to do anything about anything, I'd get them to have a look at it first. Mine seemed to get pretty twitchy about my even having read codes despite being generally pretty good about taking care of the couple things that happened under warranty.

Let them sort anything they're going to sort, then see what problems remain to be yours thereafter?

In reply to Jesse Ransom (FFS) :

I don't like going to the dealership for exactly the reason you suggest: I don't want to have to walk on eggshells with a service advisor and feign ignorance in order to get things done without a fuss. I'll never get a chance to talk to the tech at all. With my indy I can stand under the car with him and work through the diagnostics, or at least explain to him directly what I want done. That, plus the fact that everything seems to take too long at the dealership, and the hassle of having to get a loaner, and blah blah blah. The only thing I've gone there for have been recalls that could be done while I waited.

Sounds like a loose harness interconnect