PSM failure after replacing steering knuckle
02-09-2019, 12:31 PM
#1
Three Wheelin'
Thread Starter
PSM failure after replacing steering knuckle
Got PSM failure error after replacing left steering knuckle. Durametric said steering angle error. Took to independent shop and their Porsche tool said the same thing, but tech suspected the alignment was so far off that the steering angle input was being treated as an error. Did a four wheel alignment and error went away. FYI clock spring with steering wheel sensor is $95 put would have required pulling steering wheel.
02-10-2019, 11:29 AM
#3
Three Wheelin'
Thread Starter
2009 Boxster PDK w/Sport/Sport+. Stripped one of the brake caliper holes in the aluminum knuckle changing rotors and pads for the track. Put Tarrett studs in the replacement and right side knuckles. Will do the backs when we do those rotors. Would strongly suggest everyone who plans on doing any regular track days replace the brake caliper bolts with Tarrett studs. Two long steel bolts into an aluminum knuckle are too easily stripped. I understand all the GTs are upgraded to studs. You do not have to remove the caliper for pads once you have replaced the OEM pads that have the silencers on 986 and 987. 981s have an upgraded caliper with a center brace that requires removal of the caliper to replace the front pads. The rear design is still the same. Immediately got the PSM failure when we drove the car. Thought we had the alignment fairly close, but apparently not. Obviously a shop replacing the knuckle would immediately do the alignment. Surprised that both Durametric and PIWIS indicated a steering angle sensor error. Glad the Tech suspected the alignment was so far off that PSM treated the steering angle input as an error.
02-10-2019, 06:48 PM
#4
So the “knuckle” is what I would call the wheel carrier. I thought you were referring to some part of the actual steering mechanism. Definitely agree regarding the use of studs to replace caliper bolts, especially on the front brakes, which get replaced more often.