Advertise on fullfatrr.com »

Home > Technical (L322) > Help me out with the suspension on my 'famous' 4.4TDV8 L322!
Post Reply  Down to end
Page 20 of 29 <123 ... 192021 ... 272829>
Print this entire topic · 
Phoenix



Member Since: 16 May 2022
Location: Gone
Posts: 1631

United Kingdom 

Easy to do on a 4-post ramp, the bolts really should be no more than finger tight before the weight is put on the wheels, then horsed up to -'F-tight' (or 165Nm + 90deg. if you prefer) - as it's an angular tightening, I'd put a new nut & bolt in there.

Post #643833 24th Sep 2022 5:18pm
View user's profile Send private message View poster's gallery Reply with quote
GraemeS



Member Since: 06 Mar 2015
Location: Wagga area
Posts: 2278

Australia 2012 Range Rover Autobiography TDV8 Bournville

Ffrr-lover wrote:

I’m using the IIDTool which doesn’t expose the CVD values.
My IIDTool displays all CVD values. First view of the 4 height sensor voltages showed zeros for 3 sensors but then selecting 2 then 3 then all 4 again had all 4 voltages showing, so a bug in the initial display logic. Accelerometer voltages, damper duty cycles, current and lots of other values are viewable in either numeric or grahpic form.

Post #643849 24th Sep 2022 9:09pm
View user's profile Send private message View poster's gallery Reply with quote
colalowe



Member Since: 11 Jul 2021
Location: Lancashire
Posts: 104

United Kingdom 2012 Range Rover Autobiography TDV8 Buckingham Blue

So armed with the information that the height sensors have a second output to the CVD I have adjusted the height of the car up by 5mm via the GAP tool, this now uses a different part of the sensor as its 'zero' point.

my theory is that the original 'zero'point has become corrupted on one or two of the sensors in the CVD part of the sensor.

Now that I have moved the 'zero' point the sensors should give a clean reading.

Initial impressions are that the suspension is more forgiving now, I'm going to run the static test again and see if it makes any difference to the original graph I produced and run the car for a few more days to see if there is a difference or I'm just imagining it. 2012 TDV8 Autobiography Baltic Blue
Previous
2007 BMW M5 E60

Post #644093 27th Sep 2022 9:21am
View user's profile Send private message View poster's gallery Reply with quote
GraemeS



Member Since: 06 Mar 2015
Location: Wagga area
Posts: 2278

Australia 2012 Range Rover Autobiography TDV8 Bournville

Why not graph the damper height settings as they're the ones used by the damper module? Check your accelerometer static values too and again driving slowly in a straight line over a slightly bumpy surface looking for excessive voltage changes from 1 or 2 sensors.
The height sensors don't have a physical contact area so can't create a worn patch.

Post #644094 27th Sep 2022 9:50am
View user's profile Send private message View poster's gallery Reply with quote
MarianaWestminster



Member Since: 14 Jun 2018
Location: UK
Posts: 593

United Kingdom 

Some fantastic work going on in here, looks like you guys are headed towards what may potentially be the issue with our vehicles.

Having read through your posts I decided to check out my height sensors at the weekend.

Found the rear ones covered in mud around the point the attach to the lower control arm.

All this mud had trapped moisture in causing corrosion of the 'stud' which mounts on to the lower control arm.

The corrosion had bonded the rubber loop at the end of the height sensor rod to the stud which would have restricted its movement somewhat but I wasn't convinced this would have contributed to the issue.

Got it all cleaned up anyway and checked the front to find the o/s height sensor on mine is perhaps a little stiffer to move than the n/s.

Before moving on to replacement I'd like to do the static raise lower test and graph it to upload but I only have SDD and I'm not sure how to setup the data logger to do this... any ideas?

Post #644095 27th Sep 2022 10:03am
View user's profile Send private message View poster's gallery Reply with quote
colalowe



Member Since: 11 Jul 2021
Location: Lancashire
Posts: 104

United Kingdom 2012 Range Rover Autobiography TDV8 Buckingham Blue

GraemeS wrote:
Why not graph the damper height settings as they're the ones used by the damper module? Check your accelerometer static values too and again driving slowly in a straight line over a slightly bumpy surface looking for excessive voltage changes from 1 or 2 sensors.
The height sensors don't have a physical contact area so can't create a worn patch.


I will have a go at recording the values, the height sensors don't have a physical contact patch but they can still fail, below are two videos on Youtube that show height sensor faults at certain points of the measured range.
As far as I know the only way to test the CVD output of the sensor is to measure it with the Pico measurement system. I dont have that so its a bit of trial and error at the mo. Very Happy



 2012 TDV8 Autobiography Baltic Blue
Previous
2007 BMW M5 E60

Post #644101 27th Sep 2022 10:51am
View user's profile Send private message View poster's gallery Reply with quote
GraemeS



Member Since: 06 Mar 2015
Location: Wagga area
Posts: 2278

Australia 2012 Range Rover Autobiography TDV8 Bournville

Your IIDtool can show the damper height sensor values just like the height sensor values. Adaptive dynamics is very close to the top of the list of ecus in the live values selection list.

Post #644107 27th Sep 2022 11:51am
View user's profile Send private message View poster's gallery Reply with quote
GraemeS



Member Since: 06 Mar 2015
Location: Wagga area
Posts: 2278

Australia 2012 Range Rover Autobiography TDV8 Bournville

MarianaWestminster wrote:

Got it all cleaned up anyway and checked the front to find the o/s height sensor on mine is perhaps a little stiffer to move than the n/s.
Silicon spray on the pivots and on the sensor shaft might free up the movement.

Post #644108 27th Sep 2022 12:02pm
View user's profile Send private message View poster's gallery Reply with quote
GraemeS



Member Since: 06 Mar 2015
Location: Wagga area
Posts: 2278

Australia 2012 Range Rover Autobiography TDV8 Bournville

Ffrr-lover wrote:
My simplistic thinking is that while there are two outputs (height and CVD) they pull that from the same component that could be faulty.
This is incorrect. There are 6 wires going to each sensor, a set of 5V, earth and signal wires for each of the suspension and CVD sensors, with the shaft and housing the only parts in common.

Post #644113 27th Sep 2022 12:45pm
View user's profile Send private message View poster's gallery Reply with quote
colalowe



Member Since: 11 Jul 2021
Location: Lancashire
Posts: 104

United Kingdom 2012 Range Rover Autobiography TDV8 Buckingham Blue

GraemeS wrote:
Your IIDtool can show the damper height sensor values just like the height sensor values. Adaptive dynamics is very close to the top of the list of ecus in the live values selection list.


Hi GraemeS I cant see them on my GAP tool, I have the Quick list and complete list and I can only see the height values and not the active damper values from the sensor.

From my last test today the graph showed my rear right sensor at the lower setting (near the original normal height setting) is not staying flat, I have also noticed that the Lateral sensor is not staying flat as well.

The car was parked on a level flat surface and I tried with the engine running and engine off.

I have ordered a full set of Height sensors and Im wondering if swapping the accelerometers around could show if the lateral sensor is faulty (i.e. the fault transfers to the location I swap it with)



 2012 TDV8 Autobiography Baltic Blue
Previous
2007 BMW M5 E60


Last edited by colalowe on 27th Sep 2022 2:34pm. Edited 1 time in total

Post #644119 27th Sep 2022 2:26pm
View user's profile Send private message View poster's gallery Reply with quote
Phoenix



Member Since: 16 May 2022
Location: Gone
Posts: 1631

United Kingdom 

Moving the accelerometer to a different location will either confirm or deny a problem, the tolerance is 0.05VDC so if its within that, there is no point in moving it. When you say the height sensor voltage is varying, by how much? Presumably with the vehicle not moving with your comment of ign. On or off does the output to the EAS also vary?
ETA I see you have put the graphs on your post now, I can't read the scale but the activity on the rear accelerometer coincides with suspension movement and appears to be a small variation, similarly, the yellow trace is a bit 'wavy' but looks within tolerance, I wouldn't expect small variations which would be replicated on a normal road surface to give any issues, now if there is a magnitude of error greater that any other wheel moving on a normal road surface in a straight line at a constant speed, then it could be a sensor or a failing damper. Personally I'd do an A-B comparison with the EAS output from the same sensor.

Post #644120 27th Sep 2022 2:33pm
View user's profile Send private message View poster's gallery Reply with quote
colalowe



Member Since: 11 Jul 2021
Location: Lancashire
Posts: 104

United Kingdom 2012 Range Rover Autobiography TDV8 Buckingham Blue

The lateral sensor is bouncing between 0.016ms2 and 0.020ms2 not sure what that is in Volts.

The right rear height sensor V is constantly moving between 1.95v and 2.0v when it should be level like the others (in access mode) it only does it in this V range, when it goes up to say 2.85v (Off road mode) it stays perfectly flat.

The vehicle is stationary without the brake on and in neutral (this stops the brakes putting any strain on the suspension as it moves up and down)

I try the different height settings to see how the outputs change and when I noticed the Lateral sensor bouncing I wondered if it was sensing the engine running so switched off the engine to see if it made any difference (it didnt)

So all the above is reading from the height level side of the sensor as I cant get a reading from the ADM side of the sensor, what I am trying to crudely work out is that if the height side of the sensor if giving erratic readings then it is possible that the ADM side of the sensor is also giving erratic readings.

When the new sensors arrive I will fit them all and run the test again, fingers crossed I get four smooth traces on the graph at all heights, I can also then assume the ADM side of the sensor is reporting correctly as well.

Hope that makes sense, like I've said its trial and error at the moment. 2012 TDV8 Autobiography Baltic Blue
Previous
2007 BMW M5 E60

Post #644122 27th Sep 2022 2:52pm
View user's profile Send private message View poster's gallery Reply with quote
GraemeS



Member Since: 06 Mar 2015
Location: Wagga area
Posts: 2278

Australia 2012 Range Rover Autobiography TDV8 Bournville

Changing heights changes the track width so the tyres will be stretched inwards / outwards causing the height to not immediately at the required height, taking time to settle to the required height.

Does your list of live values ecus look like this, including active damping?
https://www.fullfatrr.com/gallery/albums/u...values.png

Post #644156 27th Sep 2022 9:03pm
View user's profile Send private message View poster's gallery Reply with quote
Phoenix



Member Since: 16 May 2022
Location: Gone
Posts: 1631

United Kingdom 

colalowe wrote:
The lateral sensor is bouncing between 0.016ms2 and 0.020ms2 not sure what that is in Volts.

The right rear height sensor V is constantly moving between 1.95v and 2.0v when it should be level like the others (in access mode) it only does it in this V range, when it goes up to say 2.85v (Off road mode) it stays perfectly flat.

The vehicle is stationary without the brake on and in neutral (this stops the brakes putting any strain on the suspension as it moves up and down)

I try the different height settings to see how the outputs change and when I noticed the Lateral sensor bouncing I wondered if it was sensing the engine running so switched off the engine to see if it made any difference (it didnt)

So all the above is reading from the height level side of the sensor as I cant get a reading from the ADM side of the sensor, what I am trying to crudely work out is that if the height side of the sensor if giving erratic readings then it is possible that the ADM side of the sensor is also giving erratic readings.

When the new sensors arrive I will fit them all and run the test again, fingers crossed I get four smooth traces on the graph at all heights, I can also then assume the ADM side of the sensor is reporting correctly as well.

Hope that makes sense, like I've said its trial and error at the moment.


Those measurements are hardly 'bouncing' or erratic in the real world values, yes, there is some variation but hardly anything to cause concern. There is a basic error though, you're still only reading the EAS values and assuming the ADM is getting the same values - you really need to be looking at the data the ADM is receiving, forget the IID 'tool' use a voltmeter, the signals are analogue volts DC so easily readable.

The height sensors are hall-effect sensors with a moving magnet, the output from the sensors are fed into a bit of electronics that created a linear DC voltage, it's likely that your fluctuations are due to that particular height sensor magnet moving between one hall sensor and another due to manufacturing variations (hence the banding in the graphs above) rather than an actual defect. similarly, the change in acceleration from 0.016 to 0.020m/s2 is miniscule and likely within the tolerance of the sensor, it appears that the front sensor value is a composite value of both sensors so subject to some sort of averaging / weighting - and more likely to appear 'stable'.
Personally, i think you're seeing big changes because the graph is magnifying the readings, if you were to graph across the range of acceptable signal, you wouldn't notice the slight variation you're seeing.

I think you're playing parts roulette in changing the height sensors without any solid measurements or evidence to show a defect - you'll also need to calibrate the new sensors due to manufacturing variations. But it's your money...

Post #644158 27th Sep 2022 9:21pm
View user's profile Send private message View poster's gallery Reply with quote
GraemeS



Member Since: 06 Mar 2015
Location: Wagga area
Posts: 2278

Australia 2012 Range Rover Autobiography TDV8 Bournville

The IIDtool is easy to use and it doesn't compromise the waterproof connector seals which occurs when poking a probe into the connector.

If seeing accelerometer live values on the IIDtool then you must be in the adaptive damping section and therefore the height sensors are the adaptive damping height sensors rather than the suspension height sensors. The 20A suspension system fuse can be removed then the sensor link arms disconnected and moved manually with the ignition switched on to check the smoothness of the output voltage without risk of the suspension changing height.

Post #644163 27th Sep 2022 10:35pm
View user's profile Send private message View poster's gallery Reply with quote
Post Reply  Back to top
Page 20 of 29 <123 ... 192021 ... 272829>
All times are GMT

Jump to  
Previous Topic | Next Topic >
Posting Rules
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum



Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis
fullfatrr.com RSS Feed - All Forums


Switch to Mobile site