Power steering failure/recovery

[Rahtid]

Model S 90D with current software. After a 3/4 mile drive to a local grocery store, when I tried to back the car out of its parking space, I was unable to move the steering wheel. Using a great deal of force, and moving very slowly, I was able to move the car to a relatively safe parking space away from other cars. The car seemed to be operating correctly except that the power steering was not working making the car essentially non-driveable. While moving the steering wheel the feel was “notchy” and hard to turn, almost as if the steering was actively trying to prevent the wheel being turned. Not just hard to turn as a failed hydraulic power steering unit would be.

I called roadside assistance and while waiting on hold I re-booted the main display by holding down the two knurled knobs on the steering wheel while depressing the brake pedal until the Tesla “T” appeared on the main display. At that time I was able to speak to a service technician who remotely re-booted the instrument panel display and told me that there were no errors visible. The power steering was still inoperative. He asked me to power down the car, which I did, waited about a minute and then depressed the brake pedal to turn it on again. When the car powered on, the power steering was operating normally. I was then able to drive home, albeit slowly in order to be safe should the power steering fail again.

Car was towed to service center, checked and driven overnight with no reoccurrence. They are proactively replacing the steering rack and verifying everything is OK. I will update this thread when I get the car back and a full report.

 

[murphyS90D]

The steering is electric. The first thing to check in a situation like this is the ground connections. There have been reports of a ground lug on the passenger side of the front of the car corroding and losing contact. Given your location have you driven through any streets flooded with salt water?

 

[Rahtid]

Thanks for the suggestion re the ground lug. I will follow up with the service shop. Despite the flooding 2 months ago and the recent hurricane, I did not take the car out into any flooded streets. Especially after reading a member's experience in Houston when his car was in ~20" of water. I'll know more after they replace the steering rack and check out the car.

 

[xyeahtony]

i'm glad tesla proactively replaced parts even though they couldn't find anything wrong. here's hoping it was a one-off and nothing serious.

 

[Rahtid]

Update: Tesla service was unable to reproduce the problem, so they pro-actively replaced the entire steering rack. Apparently the rack is not just a rack-and-pinion steering box with electrical assist, but also has control electronics as part of the assembly. I've had the car back for less than a day and so far its been just fine. Here's hoping it stays that way.

 

[Rahtid]

So, here it is 5 weeks after the first power steering failure and it happened again. Same conditions. After being parked/asleep, car wakes up, everything appears normal, no error messages, but no power steering. Power the car off, wait at least a minute, power the car on, everything is fine and I drive the car home. Its unlikely to be the steering rack since its been replaced with a new one. However, there are lots of other systems in the car that could be the cause. I've had Roadside Assistance open cases for engineering review and I've submitted an executive escalation case. Now to wait for a return call. Sigh.....

 

[SKRGO]

While at the SC in Atlanta charging. Another new MS owner was waiting for the techs to checkout a problem with the steering, it had locked up for a few seconds while going straight. The techs were still working on it when I left.

 

[GoTslaGo]

So, here it is 5 weeks after the first power steering failure and it happened again. Same conditions. After being parked/asleep, car wakes up, everything appears normal, no error messages, but no power steering. Power the car off, wait at least a minute, power the car on, everything is fine and I drive the car home. Its unlikely to be the steering rack since its been replaced with a new one. However, there are lots of other systems in the car that could be the cause. I've had Roadside Assistance open cases for engineering review and I've submitted an executive escalation case. Now to wait for a return call. Sigh.....

Sounds similar to Mr. Brownlee’s problem. Start around 2 min or so. Don’t recall the exact fix, but see if it sounds familiar.

 

[Rahtid]

UPDATE: So, after contacting the local service shop and filling in an executive escalation submission, I became new best friends with one of the local service techs. The initial suggestion was that the next time the power steering failed, I should contact the service team who would arrange to have the car towed to the service location. I was not to clear the problem by power cycling the car so they could examine the condition of the car with the failure. I explained that would not be acceptable since it would create a 2+ hour inconvenience in whatever I was doing at the time. I explained that I expected the engineering team, who best understand the car's systems, to review the symptoms, and let me know what the probable causes were to plan a course of action.

During the phone call I mentioned that I had just performed a software update to release "2017.42 a88c8d5". This is a mid 2016 Model S. After some research he explained that buried in that release was a "fix" to address a power steering issue. The explanation was that the steering rack was powered through an electronically resettable circuit breaker (my description based on his use of the word "fuse"). Sometimes the "fuse" would cause the steering rack to be inoperative and power cycling the car cleared the problem. I agreed to continue driving the car, albeit cautiously, since my problem only occurred after being parked.

This was 6 days ago, so its still early days, and the car is performing flawlessly. Hopefully I have no need for future updates.

 

[ScottyNZ]

I have a similar but non-identical problem. My late-model 2017 model s has intermittent power steering failure usually while driving. The steering becomes very sluggish and difficult to use. Stopping the car power and powering the entire system down and then exiting the car, locking it and then getting back in the car and unlocking it powering up again seems to fix the problem temporarily but it will usually come back from 2 to 30 minutes later. I have registered the problem with Tesla who I haven’t made any steps of the stage to try and fix at this stage.

 

[Rahtid]

Definitely a greater issue than I had. I have had no recurrence of the problem since my last post in November of 2017 and have driven about 4,000 miles since. So I’ve chalked that one up to “fixed”. I suggest that you enter an escalated problem request on the support web site to try and get some focused attention. It’s entirely possible that your right hand drive car has different software than my left hand drive one. Also, your steering assembly may have an intermittent fault, so you should press for it to be replaced, otherwise you’ll become best friends with their techs.

 

[Max Headroom]

I have exactly the same issue, Rahtid. I've escalated and have Tesla Diagnostic team looking into it. Also a mid 2016 P90D. I've been asked to pay attention to the sequence of startup as this appears to be a software issue of not turning on PS during powers up (ie. opening door, sitting, seatbelt, foot on the break, changing gear to D, etc.) . I'll post here any updates ...

 

[ScottyNZ]

Update on my ‘steering assist reduced’ problem.

Tesla took the car away and gave me a loaner, then sent my car back a day later. They told me one of the connections in the fuse area was loose. Car worked great that evening and the next day my wife borrowed it and the steering froze up on her with the same problem in a car park and she couldn’t turn the wheel and crashed into a garden island in the car park. I dropped the car back to Tesla and the problem reoccurred 4 x on the drive over (about 100km). I’m away for a month so have said they have a month to fix everything. They say they will also fix the car park damage (scratched drivers side running board) for free as it occurred do to fault with the car.

Will update when I know more.

 

[sammyfan711]

This power steering failure just happened to my mid-2016 Model S, I reversed from lunch and the steering wheel felt like it was still in park (though it would slightly turn). I didn't think to reset but just put in back in park and then reversed again and it worked.

I thought it was because of the -20 temps here in Chicago today!

Thanks for the tips above, next time I'll rest and then escalate to powering off if it still doesn't work.

 

[Rahtid]

Sammyfan711, one thing to note when powering off. I've been told that in order for everything to be really powered down, the car needs to be OFF for about 5 minutes. I also discovered, the hard way, that once you press the power off button, if you squirm in the seat or wiggle the steering wheel, it powers back on. The trick is to sit still for at least 1 minute after pressing the power off button.

 

[sammyfan711]

Sammyfan711, one thing to note when powering off. I've been told that in order for everything to be really powered down, the car needs to be OFF for about 5 minutes. I also discovered, the hard way, that once you press the power off button, if you squirm in the seat or wiggle the steering wheel, it powers back on. The trick is to sit still for at least 1 minute after pressing the power off button.

Thanks!