Sudden Loss of Power Steering WHEN DRIVING

[Skylarking]

.... To say there is no redundancy built in is just plane wrong though. When the EPS fails, there is still manual / mechanical steering control through the wheel 100% of the time.

Yes there is mechanical redundancy but is that really enough considering there may be a number of distanced failure modes? I think not.

The issue is that it seems the system may develop a fault where the assistance works against the driver to an extent it’s no longer feedback but putting a devil in control. In that sense, redundant sensors would give the system some ability to better be able to interpret faulty data and shut down, thus not putting the devil in control.

The fact that with all the workings of the EPS, Holden have provided no real technical information, they have only provided a black box description to aid in parts swapping. In such a situation it’s really difficult to know what is occurring with the system and the various failure modes that may be at play. So we are left guessing, probably like the regulators.

However, it seems like déjà vu as we’ve been here before. Holden fixed iEPS assistance with grease, then they fixed it with glue, then rack replacement. Now we see that a non VIN listed vehicle has suffering an EPS assistance failure. A failure that seemed to put the devil in control. Does that mean we again see the thin end of the wedge to a new solution being required?

Reality is that more logic is needed within EPS to be better able to detect whether faulty input is being received. Not a crap solution that considers a mechanical linkage the fall back mechanism where a driver could be over powered by the electric assistance in some failure modes.

I think Holden should get a fail and go back to school on this one, lest they put four quadrants on the sides of our heads and use us as guinea pig beta testers a.k.a. Tesla drivers

 

[Peeteone]

I've experienced the steering assistance failure too. More than once. My guess regarding what happened in your case was that you lost assistance in one direction, but not the other. This would explain why you thought the steering had "locked" to the right. Light steering to the left. Hard as nails with no power assistance to the right. This would give the feeling of it being locked up. No doubt this would make controlling the car very difficult.
To say there is no redundancy built in is just plane wrong though. When the EPS fails, there is still manual / mechanical steering control through the wheel 100% of the time.

I’m not sure about your own car/situation. Perhaps you hadn’t started your car? In that case, yes, the wheel does still allow you to turn, albeit with a lot of force. However in my situation, there was definitely a total inability to turn right. In other words the full lock to the right occurred at about 1 O’clock, instead of the usual 4 or 5 O’clock position. I’m not here to argue with non believers. I know what happened and that’s why I feel as though it is my duty to report this to the community, so that my information may potentially help someone! I think that Holden know more than they are letting on - which is why they sprang in to action to quickly in my situation with no real questions asked. They didn’t sit down with me to find out anymore information at all. As soon as I described what happened to them and advised that I could have run off the road at high speed potentially - the car was being taken away and I was handed the courtesy car. As previously mentioned. Take the information on board if you want to. If you don’t believe what I am saying, that’s ok too. But please don’t suggest that I don’t know the difference between a full lock to the right; v’s a little bit of non motorised resistance. That’s ridiculous...

 

[Forg]

Recently I contacted my local stealership about getting the steering issue resolved as I had received a letter many many months ago and had not heard back from the dealer or Holden. I was told that this issue is being resolved as owners contact either Holden or their dealers. I thought this was a bit suspect but I now have my car booked in for this issue as they had to order the kit for the issue. I also asked about whether it affected later models ie my MSE and was told that Holden are doing the earlier VF first and due to the volume later VF like my MSE will be done. It will be done in waves due to the volume of cars. Can anyone collaborate this comment about the later models.

To be honest, I thought the steering problem only affected cars up 'til 2016, so I didn't think an MSE would be affected at all.

Peeteone, I don't doubt your story in any way, but have one comment to make - it's not caused by the same problem as the one that the recall is for. Yours is something worse ... losing assistance mid-corner could be a proper recipe for disaster but if we EXPECTED it most of us would cope, but having NO steering in one direction is a totally different (and scary) kettle of fish!!

 

[Skylarking]

@Forg, we don’t really know if Peeteone’s fault occurrence is something entirely different to the EPS assistance failure or simply another manifestation of the same basic underlying issue (corrupt signal to the EPS control system).

Keep in mind that the EPS assistance failure root cause was deemed to be fretting corrosion of the motor connector pins (where the consequence of such fretting corrosion must ultimately be seen as corrupted signals to the EPS control system; sadly not spelt out in such a way by Holden/GM).

As is, I believe that the connector in question has the steering angle/torque signals pins within. Thus any wiring fault or sensor fault could also cause corrupted signals to be oddly interpreted by the EPS control system. Such conditions could lead to potentially multiple types of faulty behaviour, not just a simple loss of assistance. But we don’t know as there is no detailed technical info on the system itself, it’s just a black box.

As I’ve stated before, we just don’t know whether all fault cases have been considered in the analysis of the EPS failures modes seen to date. And we don’t know whether the only outcome is loss of assistance. It’s just a convenient truth for Holden to take a simple view of only assistance failure and downplay the whole situation.

I still believe that the system can fault and apply forced assistance in a way that fights the driver (which increases danger exponentially to a simple loss of assistance). Such a scenario would explain one of the first reported instances of EPS failure by a taxi driver down under where he reported he could not turn the steering wheel at all. It would also explain Peeteone’s scenario.

The end result is that we have a frightening situation with an unknown class of fault cases within a electronic system that has no electronic redundancy. To have a fault case where assistance is lost, having mechanical redundancy is helpful. But to have a fault case where active power assistance fights against the driver, having mechanical redundancy is a falsehood that one day the regulators will wake up to.

It’s something that simply can’t be dismissed in the way that Holden seem to have done. The whole situation of owning a powerful vehicle where we can’t trust the steering is simply frightening kettle of fish (if the scope is indeed as wide as is now being implied).

This situation simply does not seem to be over as there is more that needs to play out before all situations are understood. If Holden/GM had brains, they’d be looking at every failure mode for all components within the EPS and exercising all the control system inputs and outputs according to these failure modes.

 

[426Cuda]

To be honest, I thought the steering problem only affected cars up 'til 2016, so I didn't think an MSE would be affected at all.

Peeteone, I don't doubt your story in any way, but have one comment to make - it's not caused by the same problem as the one that the recall is for. Yours is something worse ... losing assistance mid-corner could be a proper recipe for disaster but if we EXPECTED it most of us would cope, but having NO steering in one direction is a totally different (and scary) kettle of fish!!

I lost mine half way through a large roundabout the second time. Doing about 60 k's. Not only did I cope, I drove the car downtown, in traffic.

 

[426Cuda]

Yes there is mechanical redundancy but is that really enough considering there may be a number of distanced failure modes? I think not.

The issue is that it seems the system may develop a fault where the assistance works against the driver to an extent it’s no longer feedback but putting a devil in control. In that sense, redundant sensors would give the system some ability to better be able to interpret faulty data and shut down, thus not putting the devil in control.

The fact that with all the workings of the EPS, Holden have provided no real technical information, they have only provided a black box description to aid in parts swapping. In such a situation it’s really difficult to know what is occurring with the system and the various failure modes that may be at play. So we are left guessing, probably like the regulators.

However, it seems like déjà vu as we’ve been here before. Holden fixed iEPS assistance with grease, then they fixed it with glue, then rack replacement. Now we see that a non VIN listed vehicle has suffering an EPS assistance failure. A failure that seemed to put the devil in control. Does that mean we again see the thin end of the wedge to a new solution being required?

Reality is that more logic is needed within EPS to be better able to detect whether faulty input is being received. Not a crap solution that considers a mechanical linkage the fall back mechanism where a driver could be over powered by the electric assistance in some failure modes.

I think Holden should get a fail and go back to school on this one, lest they put four quadrants on the sides of our heads and use us as guinea pig beta testers a.k.a. Tesla drivers

To answer your question Skylarking: Yes, the mechanical redundancy has been more than adequate for ME to drive MY car safely each time I've experienced the EPS fault. Satan never materialised.
But, if the totally hypothetical situation you describe occurred with the devil flinging the wheel left and right, fighting the driver at every turn occurred, that would be a different and very dangerous situation.

 

[426Cuda]

I’m not sure about your own car/situation. Perhaps you hadn’t started your car? In that case, yes, the wheel does still allow you to turn, albeit with a lot of force. However in my situation, there was definitely a total inability to turn right. In other words the full lock to the right occurred at about 1 O’clock, instead of the usual 4 or 5 O’clock position. I’m not here to argue with non believers. I know what happened and that’s why I feel as though it is my duty to report this to the community, so that my information may potentially help someone! I think that Holden know more than they are letting on - which is why they sprang in to action to quickly in my situation with no real questions asked. They didn’t sit down with me to find out anymore information at all. As soon as I described what happened to them and advised that I could have run off the road at high speed potentially - the car was being taken away and I was handed the courtesy car. As previously mentioned. Take the information on board if you want to. If you don’t believe what I am saying, that’s ok too. But please don’t suggest that I don’t know the difference between a full lock to the right; v’s a little bit of non motorised resistance. That’s ridiculous...

Nah, I've experienced full EPS failure numerous times while driving now.
Not sure how you think I'd have EPS failure and still have steering without the car started?
You may not be here to argue with non belivers. But, you're quick to do so.
Stating I have "suggested" something about your knowledge (heaven forbid)? I didn't "suggest" anything of the sort. I simply had a guess at what I thought may have had happened, in the situation you described. I also noted the steering to the right being "hard as nails", not " a little bit of non motorised assistance." Branding someone a non-believer, mis-quoting, or putting words in someone's mouth because they've posited a different view to your own as to the cause... now that's what I'd call being a little petty if not ridiculous Presh.

 

[Peeteone]

Sounding very defensive and argumentative there. I’m just reporting on something that actually happened. You’re sitting here picking it to shreds and having a go. Maybe it’s time for you to get out of the house a little; rather than sitting on the pc analysing people’s comments! It’s summer ... the sun is shining. Try it!

 

[Trevor loves holden.]

No sun in Melbourne for 7 days now straight, still waiting for summer well spring for that matter. My nephews cruze went into limp mode as he was low on coolant he lost power steering and all the Christmas lights came on. Terrible designed which can cause a accident.

 

[426Cuda]

Sounding very defensive and argumentative there. I’m just reporting on something that actually happened. You’re sitting here picking it to shreds and having a go. Maybe it’s time for you to get out of the house a little; rather than sitting on the pc analysing people’s comments! It’s summer ... the sun is shining. Try it!

Fair call.