[SOLVED] Steering angle sensor error (trifecta light)

[tomrdy]

TLDR: Check out these whack readings I got for the steering angles! Thoughts? Does anyone know if a reset will help? Currently have the trifecta lights
____

Hey guys, I've had the classic trifecta of warning lights in the past (Tyre pressure + DSC + Handbrake) but they've come ... and resolved themselves with me doing nothing more than the engineer's fix (turn it off and on again ).

I've seen a lot of members have the same lights and it ended up being the brake pressure sensors - which I had previously anticipated as my issue eventually and was prepared to change them out when the time came.

The lights came back on today and the steering felt quite funny - almost like the EPS was bit confused. So I checked the codes and sure enough there were some for the steering angle sensor.

NOTE: I had the sensor "reset" by a garage when I had the persistent lights (wouldnt go away) when I first had the car which solved it for long enough that I can't remember how long.

Checked the data coming through on the C110+ and check this out...

Center point was fine 0.0... and turning it to the left was completely fine (from 0 to full lock A-OK):



Turning to the right however... (I turned it slightly, pretty much same as I had to the left so expected a few degrees):



Behaviour is exactly the same as seen in this owner's clip: https://www.youtube.com/watch?v=eFGNdQKGqPs which makes me wonder if this is the C110+'s bug or my (and the video owner's) sensors are bugged.

I'm hoping to set up INPA soon so I can cross check (and reset the sensor) but thought I'd query the forum and see if anyone has any thoughts/experience with these readings?

 

[Anonymous]

I had the same 3 lihgts, and the steering angle error. Took about 30 seconds in INPA to re-calibrate and that was that. Never seen again.

Mine appeared a few days after changing track rod ends

 

[tomrdy]

I had the same 3 lihgts, and the steering angle error. Took about 30 seconds in INPA to re-calibrate and that was that. Never seen again.

Mine appeared a few days after changing track rod ends

Thanks for chiming in Greg - sounds promising for once I get INPA set up

 

[biojo]

Yeah ive had same, re calibrate it then it doesnt come back, its only ever come one previously after battery was disconnected and when i was working in car and had radio on for a long time

 

[tomrdy]

Update on this.

Got INPA working (thanks to a member for pointing me in the right direction - saved a MOUNTAIN of time!) and turns out that the angle readings are correct - I guess the C110+ has an issue interpreting.

Angles read fine throughout each way as expected but was about -2 degrees off center. Ran the reset and went for a nice drive.

Was fine until I got near home and I went through the usual roundabouts :!: :!: :!:

:headbang:

Got home. Read the errors, reset it again and drove out specifically to those roundabouts... and nothing happened.

In the errors, the only one that didn't seem like it was just saying "SOMETHING IS WRONG!!" was this:



Quick google translate: "difference of more than 90 degrees detected"

Because it's wildly inconsistent with error-ing (though more frequent right now), I am thinking:

• Dirty/worn contacts on the sensor (aka replace)

• Wheel speed sensor faulty/dirty - I think this has been reported to mess with the DSC as well? Haven't been able to find a specific error for any of them though

• One other thing I'm thinking of trying is resetting the Lateral Acceleration Sensor since its (to my memory) 100% mid right-hand turns that the error pops up. Could be related?

Other errors in the DSC modue ("steering sensor internal"):


Cleaning or replacing the SAS is the last thing I want to try but from reading this morning, looking more like the obvious problem.

 

[tomrdy]

Started having a look at the sensor physically itself yesterday and tried the engineer's reset - unplugged everything, gave it a few taps and plugged it all back in.

I jacked the car up (so I could turn the wheel freely) and ran INPA to check the data coming through on the sensor and it was 100% all fine both ways (both sides equal turn amount as well so rule out any rack + tie road alignment possibilities). Did the reset on the SAS + LAS and took the car for a run.

All was well until again, right hand turn with the wheel at 90+ degrees.

Pulled over to look on the C110+ and see the angle now stuck at "!1440". Cleared the codes (all mentioning SAS only), turned off the car and back on - all is well again.

Reading almost everything I can find on the forums including the E46 crowd and there's a range of causes from wheel speed sensors, ABS pressure sensors, headlamp levellers (???). Also received sound advice from someone - "maybe go with the obvious thing the fault codes are telling you first.". Makes sense so I'll do that.

Plan of attack now is to order the SAS repair kit (at about $150 AUD shipped) which has a new plate + brushes and rebuild the sensor. Undecided if I'm going to pull the rack out or try and do it in-situ (link). I am quite dainty but even having a LOOK at the sensor yesterday was a bit back breaking :rofl: Suppose no harm trying the former first.

If that doesn't work, I'll then order the sensor replacement kit (runs about $400 AUD). Not 100% sure how to code it but I have access to PA Soft which I've seen others have used to place the VIN in.

I will keep this thread updated and add more pictures in. Hopefully it will have a "SOLVED" at the front in the future at some point and save someone a headache.

if THAT doesn't work... I suppose I'll need to look into the yaw/lateral sensors as the error only ever comes up in motion (and on right handers). It did pop up while near crawling speed in the carpark the other day though - but also turning right.

 

[tomrdy]

Curiosity got the better of me today and I decided to try and get more data - and may have ended up fixing it :rofl:

Pulled off some wheel speed sensors, cleaned them and reset all faults and ran the car just to eliminate. Errors as before... except....

TODAY finally the fault was completely consistent - left turn (moving or stationary) at ~75 degrees the error would flag up. For anyone who has experience troubleshooting code, repeat-ability in a bug is a godsend. I had INPA running and could see the exact point that the angle input stopped. This was a good sign because it meant to me with near certainty that the SAS was the culprit.

Decided to take a serious look at the SAS to try and decide which approach to take later with the rebuild (column out or not) and noticed that my sensor didn't have a snap ring like it says on PelicanParts. Odd.

I proceeded to (because curious) try and slide the SAS off the 2 hooked notches. Then, once it came free, I realised I could probably undo the wiring clip and spin the sensor around - and be able to undo all the screws and split it apart while still in situ to inspect the brushes.

So i did that.





To my delight (as it is now a 99.9% certainty the issue with the SAS and nothing else), the brushes did indeed look terrible! The picture is a little deceiving - the upper brush is actually half the length and what you can see is actually grease + fragments.



So I cleaned up some of the metal shavings with a magnet and proceeded to bend the worn brush (1 on each pair it seems) outwards a bit.

Reassembled everything; clipped the sensor back in and zero'ed the steering in INPA, as well as cleared all faults.

Went for a drive.

....

....

No errors! So for now, I am hopeful this is a credible temporary fix - the brushes will wear again; and the bending-out-part could be very inconsistent. The advantages are though that nothing had to come off the car besides the footwell trim. Doing it again I think it'd take me 30 minutes tops just because of the awkward positioning.

I plan on still ordering the rebuild kit with new brushes but hopefully this will sort it for now

Will report how this goes.

 

[ph001]

Great info and fix (even if temporarily). Thanks for sharing #SAS

 

[tomrdy]

Happy to report that I did a bit of driving today and absolutely 0 issues - good thing too as its pouring down now so DSC and TC very welcome.

I'm going to mark this as FIXED and recommend (if you are so inclined) to give this a go before shelling out on a new SAS/rebuild kit since all it will cost you is a small torx screwdriver and some neck + back pain .

 

[Jezza21]

I proceeded to (because curious) try and slide the SAS off the 2 hooked notches. Then, once it came free, I realised I could probably undo the wiring clip and spin the sensor around - and be able to undo all the screws and split it apart while still in situ to inspect the brushes.

How on earth did you get it off, my fingertips are in shreds after pressing the 2 clips together to try and slide it off

I can’t feel any movement in twisting, so I presume pressing the clips and slide over them is the only way!?

Help!

 

[CRAIGO]

Did this today myself and will clean up the brushes and bend them up slightly for better contact. The two prongs are horrible to press in. I found it easy to lean into the footwell and use my left hand to push the SAS down the steering column while pressing the two plastic release prongs using my right arm. You do need to apply some pushing force with your left arm over the SAS but be prepared for it releasing as the momentum of it releasing could damage the electrical connector. It's best to snip off the two tie wraps holding the connector wiring in place and releasing the connector prior to trying to remove the SAS to prevent damage.

My brushes look exactly like the ones above so I'm hoping for the same fixed result once cleaned up and put back together. I use BMW scanner 1.4 to reset this code.

 

[bigwinn]

Did this today myself and will clean up the brushes and bend them up slightly for better contact. The two prongs are horrible to press in. I found it easy to lean into the footwell and use my left hand to push the SAS down the steering column while pressing the two plastic release prongs using my right arm. You do need to apply some pushing force with your left arm over the SAS but be prepared for it releasing as the momentum of it releasing could damage the electrical connector. It's best to snip off the two tie wraps holding the connector wiring in place and releasing the connector prior to trying to remove the SAS to prevent damage.

My brushes look exactly like the ones above so I'm hoping for the same fixed result once cleaned up and put back together. I use BMW scanner 1.4 to reset this code.

Did the same to my 3.0 today

Pic attached for the bushes which were poor

 

[bigwinn]

I found that if you used your fingers to compress the two clips either side of the column, a long screwdriver behind the SAS popped it off down the column

For reference the torx are T6 which are a PITA

 

[Jonc]

Hi matey,
I have a similar error where I have the steering twitching and I am not sure if this is the same.
https://youtu.be/BjZm8o1_Y6k
Any thoughts

 

[bigwinn]

Hi matey,
I have a similar error where I have the steering twitching and I am not sure if this is the same.
https://youtu.be/BjZm8o1_Y6k
Any thoughts

No I’d say that’s similar to the issue we saw

enuff_zed

with the torque sensor? What do you think?

 

[enuff_zed]

Unread post by bigwinn » Tue Mar 28, 2023 8:18 pm

Not sure actually. For a start we had a torque code pop up.
Also, turning the wheel to the right all was good. Turning very gently to the left was ok, but turn it quickly to the left and it failed the EPS and kicked back, indicating it didn't like the sudden torque loading. Never any of that random twitching.
That video is telling me the EPS ECU is getting continual inputs telling it that the steering column is turning and its trying to adjust for them all.
As always................... what codes are there?

 

[Jonc]

To be honest I have no idea. I am dusting off the old laptop so I can plug her in and have a look at the codes.

 

[DarkBMW]

I know that people have changed the brushes themselves in this sensor. New counters were taken from the ERA 550485 sensor (VAZ / LADA 2112) - the price is about 10 GPB + shipping