BMW Steering, Brake Simultaneous Failure with Bad Battery?

bmw
550

#1

My 2011 550i with 53K miles has this weird problem. It was towed due to a stall following loss control of steering and brakes - a safety issue. After driving for 30m-1h I suddenly got multiple different warning lights before I lost control of steering (stiff like a dead body) and brakes following which the car stalled. This is the third time this had happened in the past 6 months.

The first time it was towed to Advantage dealership and I was told it was a bad battery which did not make sense but the car was running after battery replacement so I took it home. The second time the dealership was closed - I was able to start the car a few minutes later and took the risk of driving home. The next day when I brought it in, I was told that the car was running and that they could not run any diagnosis. Thereafter, the car ran fine for 3 weeks before it happened again. This time I could restart it but the car would only move a few feet before stalling.

The service center has replaced the battery and alternator and say the car has no issues. I had earlier asked the service adviser and service manager
to diagnose the safety issue first before replacing the alternator - otherwise they would not be able to replicate the safety issue. But I have been told that the warnings and car behavior is normal under low voltage conditions. I have also heard inconsistent messages from the dealership that indicates they do not understand or know how to diagnose and resolve this critical issue.

However, no driver should ever lose control of car under any mechanical circumstances. This is either a design (BMW) issue or there is a defect in my specific car that needs to be determined and fixed.

Are there others who had a similar experience and if so how did they address this?


#2

I submit that your car stalled first. That causes you to lose your power in your power steering and brakes.


#3

No the stall happened at the very end. Warning lights, steering and brake failure and then stalled. I was coming back home and turning into my neighborhood street when the steering stiffened up- I nearly hit the opposite side curb.


#4

I don’t have an answer to your issue. Some time ago, I suspected battery problems on one of my cars. I purchased this type of monitor (not exactly the same) to keep an eye on my battery while driving. Maybe too late for you, but something to consider in the future. These things are very inexpensive.


#5

I’m thinking along the lines of @oldtimer_11- the warning lights are a sign of the engine stalling. Without your engine running, you are going to lose power assist to the steering, and eventually the brakes.

Beyond that,. it sounds like you are having issues finding a mechanic that will take some time with your car to really dig. assuming your battery and alternator are ok, I would look very closely at your battery cables. Make sure they are clean, tight, and not rubbing anything. Follow them as far as they go. Check the wires at the starter for corrosion.

Saying “However, no driver should ever lose control of car under any mechanical circumstances.” is good thinking, but unfortunately not practical. there are several mechanical failures that can cause loss of control. Proper maintenance and Preventative Maintenance inspections can catch the majority of these items, but parts still break. That’s why mechanics still have jobs. :slight_smile:


#6

You are right. They are not willing to find the source of the issue. It is not just battery and alternator. One can steer the car without having power but not being able to steer suggests a different though possibly related problem


#7

You were able to steer. It was just really stiff because you were going slow. Is it possible that the engine stalled, but you were distracted by all the warning lights and didn’t realize it had stalled until you noticed the steering and brake pedal getting hard?

The reason I ask is that power steering is really only noticeable at low speeds. At higher speeds you could disable power steering entirely and never feel the difference. And power brakes work on a vacuum, which means that after the engine turns off, there’s still enough vacuum available for the brakes to feel completely normal the first time you press them.

So it could have stalled and still felt normal for steering and braking, but the first time you hit the brake pedal eliminated the vacuum so that the second time you hit it, it was stiff. Meanwhile, that first braking session slowed the vehicle down enough for the lack of power steering to become apparent.

Now, all that said, I agree with you that it probably isn’t the battery or the alternator unless there was a loose wire somewhere - in which case they probably fixed the loose wire when they connected the new battery and alternator.

I can tell you that my mom has a 2014 X3, and… Well, no offense, but as far as electricals go, BMW sucks. Whoever’s doing the electrical design over there has his head in the clouds. He designs as though he thinks the car will always be operated in a sterile laboratory environment, and so there aren’t any “what if this goes wrong” contingencies. This is why mom pairing the wrong cell phone to the car killed the radio, the navigation system, and the climate control.

I can also tell you that in her experience, everything that goes wrong with the car is blamed on a bad alternator and battery. When she brought me in with her once and I pressed the tech to explain why a battery capable of starting the car was too weak to unlock the doors, he just kept repeating “it’s a bad battery sir.”

In short, I’ve come to the suspicion from hers and other peoples’ experiences that BMW is not putting much thought into failsafes, and they’re not putting that much thought into training their mechanics to actually diagnose problems.


#8

If you can design a power steering system and power brake system that work equally well with or without power (without adding much weight or expense), I’m sure the auto companies will buy it from you. Good luck with that!


#9

They have already been invented.

Electric power steering can work with the engine off, it runs from the battery. Its been available for almost 20 years.

The same for brakes. Mercedes-Benz developed an ABS/Booster/Stability Control system that does not rely on engine vacuum or power steering pressure (Hydroboost) to operate the brakes. It is a servo-hydraulic system that is “brake-by-wire.” Installed on some M-B models about 12-15 years ago


#10

How do you know this?


#11

I friend of mine had a fortune from his new business and bought a brand-spanking-new X6 few years ago and had nothing but troubles with it for year and half, symptoms very similar to the ones OP describes.

After having it to dealer repair facility something like 10 times and replacing battery/alternator repeatedly, he was told that he is not driving enough to charge the battery and he is supposed to drive at least 30-40 miles on every trip to compensate for energy draw for all fancy-power-everything.

At that point he already had engine stalls when getting on the exit ramp and barely missing concrete barrier, passing the truck and stalling just in front of it, etc…, so he sued BMW… In the end, they offered to buy back the vehicle, $20K or so less than original price, never agreed to admit any flaw in design or safety concern, not to mention they were much less than friendly.

He is back to Infinity, same body as his old beaten Murano he did not have any major headache with.


#12

Oh yeah! Mom’s heard that a lot. I really like how the battery is good enough to start the car, and run it for 20 miles before it goes haywire, but somehow it’s all your fault 'cause the battery isn’t sufficiently charged. Sounds like BMW needs to spec a charging system that can keep up with load if that’s the case.

Well, in fairness, he did sue them. If you sue me, even if I’m in the wrong, I’m not exactly gonna invite you over for cocktails, y’know? :wink:

But yeah. I told Mom to get an Acura, but that wasn’t a “prestigious” enough marque for her, so I rolled my eyes and told her to get the Porsche SUV because it’s much better than the BMW, but she had been dreaming of having a car with that roundel on it since she was 20, and so she ignored my advice and has been irritated ever since.

It’s really a shame, because her car drives beautifully when it’s working. If BMW would put a little R&D into quality and reliability instead of devoting it all to “what stupid geegaw that nobody needs can I jam into this thing to brag about on sales brochures” research, they and their customers would be better off.


#13

well, paying that $$ premium, I would expect the manufacturer to “keep their face” so that other people keep buying it.
from what that “happy owner” told me, once he researched what other owners were saying, it was pretty much all about “never again” in different variations.


#14

The engine was running when this happened. It was sequential - warning lights, loss of steering/brakes and then stall. Happened 3 times in 6-mos!


#16

Power steering does not mean that you cannot steer without power. It just becomes much harder like it used to be before power steering was invented. Loss of power should not cause stiffness similar to steering loss.


#17

I had a rental Kia last year.
At one point I was driving down the highway when the car lurched like it had hit ice (summer) and then dash lights came on and the steering got very hard.

I managed to pull over to the side of the road, shut the car off then restarted and all was back to normal.

A few minutes later it did it again so I performed the same action but now the dash lights stayed on and the steering stayed stiff.

I ended up taking pictures of the dash to have a record of the lights but also looked them up in the owners manual. I found the lights were for the electronic steering and the stability control.

I have no idea what the problem with the car was, it was a rental, however have you recorded the lights that come on? If the lights come on prior to the car stalling then they are telling you something. If they come on after stalling then dash lights are pretty normal in that case.


#18

Yes, I did take photos of the warning lights that came on before the stall.


#19

No, loss of power steering will cause the steering to be much worse than it would be with manual steering. And how did you know the engine was still running?


#20

Assuming that you are referring to the Infiniti marque, that brand still lags far behind Lexus, Toyota, Honda, and Subaru in terms of both reliability and durability. If somebody is seeking better reliability stats than BMW, I submit that Infintii is probably not the marque upon which one should focus.


#21

well, not my choice anyway, he liked his Murano when he could not afford more, so he stepped into similar body in Infinity line, lazy choice

if it was my choice, I would vote Lexus or Subaru