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"Power Steering Malfunction" message

15K views 16 replies 10 participants last post by  Tree95  
#1 ·
Returning from a camping trip in Zion National Park, my van popped up "Power Steering Malfunction. See Owners Manual" on display between the Odo and Tach. It's a bear to drive without any power assist.

Ironically, almost exactly a year ago, as I was returning from a camping trip in Zion, within 50 miles of today's issue, I had the same thing happen. This was on highway US95 in Nevada northbound between Tonopah and Hawthorne. Out in the middle of nowhere. I had no real options but continue. Last year, I stopped at rest stop, and when I restarted the van, the power steering had returned. 10 minutes later, same thing. I stopped in Hawthorne for gas, and again, when the van was restarted, the power steering was back and continued doing is job for the 200 miles left to home.

I took the van into the dealer, and they replaced the entire steering rack assembly - the rack, the electric motor, and the control electronics.

Today, in the same stretch of US95, about 30 miles south of Hawthorne, same thing! I stopped at the exact same gas station in Hawthorne, and when I restarted, the power steering was back, and remained functional for the rest of the drive home.

With that long introduction, I have a suspicion/theory/guess as to a contributing factor. This stretch of road has grooves (rumble strips) cut into it along the center line, just as many roads do on their outer edge, to warn drivers that they are out of their lane. The grooves on this stretch are very aggressive. The speed limit is 75. It's two lanes, pretty straight, with a decent number of trucks and campers/RVs doing less than the speed limit. The grooves are so aggressive, that passing on that section definitely requires two hands on the wheel as the van's tires cross. The steering components take a beating as one front tire and then the other cross over a few seconds of very rough road at 60 to 80 miles per hour.

I'm wondering/guessing/theorizing/pulling things out of dark orifices that the pretty violent rapid "chatter" of one or the other of the front tires crossing over these things is causing the power steering controller to be confused into thinking there is some sort of failure in the power steering unit. Last year, I'm pretty sure the 'malfunction' message appeared while I was cruising along in my lane, but today, the message occurred as the left tire hit the rumble strip when I was pulling left to pass a semi.

It seems like too much of a coincidence to have this same reported malfunction a year apart, 15k miles later, on two different steering racks, on the same section of road under similar conditions.

I don't think I'm going to take it into the dealer this time. Last time, the replacement was $4100 list price. I'm not sure anything's actually broken other than confused firmware in the power steering controller and/or stability control and/or lane assist and/or all of the other computers monitoring the van's dynamics. I think some module is observing readings it wasn't programmed for and is shutting down the power steering with a false alarm fault.

Or, am I just kidding myself.
 
Discussion starter · #12 ·
Earlier this month, while driving I80 west of Salt Lake City, traffic lanes were diverted left in a construction zone. While crossing uneven concrete pavement, I heard the warning beep, saw the "Power Steering Malfunction" message, and lost power assist. That was scary as the lanes diverted right again quickly, and I was struggling to steer the van.

I filled out a complaint at the National Highway Traffic Safety Administration website today detailing the four failures on two different steering racks. I also included links to this thread and a similar one started by @Vanz Power Steering Malfunction

Maybe something will come of it. Maybe not.
 
Discussion starter · #17 ·
Any advice is appreciated.
if the power steering is working again, then just ignore it.

I'm one of the folks with a 2016 Metris who's power steering fails after cattle guards or aggressive rumble strips. I have to carefully pull over, shut down, lock the car and wait 10 minutes for everthing to power down. Then it's good as new until the next cattle guard.

I'm pissed I spent $4000 to replace the steering only to have the new one do the exact same thing!

Stupid German software engineers.