Member Since: 26 Oct 2013
Location: Liverpool
Posts: 690
Latest suspension woes
Our D3 has been pretty well behaved lately (famous last words!)
Spent all Friday morning loading it up for a long weekend away camping with the family. Boot was loaded to the ceiling and we had our roofbox on the top, plus 2 adults and 2 kids inside.
Drove around Liverpool fully loaded doing a few last minute errands with no problem at all.
Headed out of Liverpool on the M62 and got about half way to the first junction when suddenly the dreaded bong and "suspension fault, max speed 30mph" appears. It then drops to it's bump stops amidst a lot of effin and jeffin from me and the Mrs. Turn it off and on again and the faults go. Tried to continue and got a bit towards the next junction when it happened again. Long story short, had to head home and repack everything into my A6 and head off again.
Now I'm back home I spent a bit of time last night investigating and these are the curious findings:
Suspension works perfectly raising and lowering when stationary and on the move
I can drive all day around town with not a single issue
As soon as I go over ~55mph the issue occurs
When it goes wrong, the car suddenly thinks the front and rear left side height sensors are playing up, showing this image:
It logs the supporting fault codes of "C1A74 - Rear left height sensor mechanism" & "C1A03 Front left height sensor" but ONLY when I hit ~55mph plus...
I also get "C1A07 - Cross articulation".
Full list of faults logged, after I first cleared everything and re-created the fault conditions:
U0010 - Medium speed CAN communication bus
U0132 - Lost communication with ride level ctrl module / Lost communication with suspension ctrl module A
C1A74 - Rear left height sensor mechanism
C1A03 - Front left height sensor
C1A07 - Cross articulation
U0421 - Invalid data received from ride level control module
The other thing I've observed is that at Standard height, even though the car is dead level (measured and callibrated) the 4x4 info shows the four wheels as being slightly off:
I had problems callibrating it, as the front right and rear-left were miles out...
The car has new front and middle valve blocks, as well as Arnot AMK compressor, all within the last 6months or so.
What am I looking for that would cause this but be speed related? Something simple like four wheel alignment? A speed sensor? Is it actually the height sensors being speed sensitive?!
Any advice welcome as I'm completely stumped!Cheers,
Gareth
'57 D3 2.7 TDV6 HSE gone and soon to be forgotten!
‘15 D4 3.0 SDV6 HSE Luxury
'64 Audi A6 3.0BiTDi Quattro S-Line Black Edition with lots of toys
30th May 2018 2:33 pm
highlands
Member Since: 11 Jan 2010
Location: NW Highlands
Posts: 5095
I would check the multiplug/loom behind the NSF wheel arch.
Not sure why it'd be specific to high speed unless turbulent air is causing loose/corroded wires to move.Black 05 TDV6 HSE Auto
Grey 05 TDV6 HSE Auto (Gone)
54 TDV6 SE Man (killed by me )
30th May 2018 2:58 pm
L319
Member Since: 14 Dec 2013
Location: Herefordshire
Posts: 2080
A few years ago I had mine dropping on bump stops, but only when towing a trailer, could be in a straight line or cornering ,usually at the 50mph mark. Not sure now what messages came up but the steering angle sensor was out by about 10 degrees ,which the garage didn't believe would cause this problem but was the only thing they could find wrong. Re calibration sorted it.
30th May 2018 3:43 pm
Pete K
Member Since: 15 Jan 2016
Location: GL
Posts: 10360
don't you just love the suspension on these...
Maybe it only runs this test/check above 55MPH
Is the car only used around town at slow speeds usually?
I think your onto something with the pictures. Maybe that is what Cross articulation means.
I guess you need to re calibrate it, and if that doesn't help, fudge the cal figures to make the picture a little better (but not so far out the car is dangerous) and see if that clears the fault. It would be interesting if nothing else
It might be level but if one of the height sensors is near the max limit tolerance then fully loaded it might throw it out, check this and also as suggested check the SAS for adjustment.
Flack
30th May 2018 5:59 pm
wizbongre
Member Since: 26 Oct 2013
Location: Liverpool
Posts: 690
I've just re-callibrated and will take it on a test run in a mo, once SWMBO is settled from work.
@Flack, one of the sensors is indeed at max adjustment (45 out of 50 on the Nanocom) to get it all level, so maybe that is the cause. If you recall the last time you were here we had some "issues" with the height sensors and callibrating it, so maybe I need to bite the bullet and invest in some new sensors...Cheers,
Gareth
'57 D3 2.7 TDV6 HSE gone and soon to be forgotten!
‘15 D4 3.0 SDV6 HSE Luxury
'64 Audi A6 3.0BiTDi Quattro S-Line Black Edition with lots of toys
30th May 2018 6:02 pm
wizbongre
Member Since: 26 Oct 2013
Location: Liverpool
Posts: 690
New sensors fitted - problem solved Cheers,
Gareth
'57 D3 2.7 TDV6 HSE gone and soon to be forgotten!
‘15 D4 3.0 SDV6 HSE Luxury
'64 Audi A6 3.0BiTDi Quattro S-Line Black Edition with lots of toys
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