The suspension has been sagging slowly over a couple of days on one side. I have recently replaced the front air struts. The rear sat on its bump stops and came up with a suspension fault. I have attempted to do some research and use my Gap IID tool. On checking the voltage on the height sensors the rear left is lower than the rest. Can you just validate that this is probably the issue? Do I need to calibrate the suspension after changing, I haven't got round to it yet for the front, but I can see a disparity on the readings. I also haven't got as far as working out how to do that yet, I'm attempting to teach myself about the car, as you can probably tell...!

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Not sure if yours will be the same as mine but this is what I found with my 2006 L322 which wouldn't calibrate. Spent about 20 hours on and off trying to sort this out.

Likely the brackets are bent.

Drop the car onto its bump stops and see what the voltages are readying then.

I can't remember which way round the front and rear sensors work so some of this is interchangeable.

The front sensors go from 5v to 0v as height increases.
The rear sensors go from 0v to 5v when height increases.
Fronts should both be the same value give or take.
Rears should be the same.
Front left and rear left should add up to 5v, same for the right.

On mine the front right was way out and just needed the bracket bending to get the reading right, after that been faultless since.

Its also possible all your sensors work the same way in which case your bracket may just need a tweak to get it reading the same. Can test the bracket theory by unclipping the sensor from the suspension arm and move it full range to see what voltages you get. If the voltages are right then reconnect it and just bend it.

I think it was on its bump stops when I took the reading. I’ll take a look at the bracket and maybe unclip. Thanks for this. 2012 Westminster Aintree/Ivory 4.4TDV8

Jason66 wrote:

Do I need to calibrate the suspension after changing, I haven't got round to it yet for the front, but I can see a disparity on the readings. I also haven't got as far as working out how to do that yet, I'm attempting to teach myself about the car, as you can probably tell...!

Nothing to lose, I prefer free fixes over costly ones 😂

Ramblin Man wrote:

Jason66 wrote:

Do I need to calibrate the suspension after changing, I haven't got round to it yet for the front, but I can see a disparity on the readings. I also haven't got as far as working out how to do that yet, I'm attempting to teach myself about the car, as you can probably tell...!

This will help:

https://youtu.be/9ot3L4CHPd4?si=jG2qrqGXISW6aeMZ&t=20m

FWIW : I would also suggest a Hunter 4x4 wheel alignment. After I had mine done at GlenRands it was like driving a different vehicle.

and remember to use the GAP IID tool to put the car into "Tight Tolerance" mode before you do the wheel alignment

Ramblin Man wrote:

Jason66 wrote:

Do I need to calibrate the suspension after changing, I haven't got round to it yet for the front, but I can see a disparity on the readings. I also haven't got as far as working out how to do that yet, I'm attempting to teach myself about the car, as you can probably tell...!

This will help:

https://youtu.be/9ot3L4CHPd4?si=jG2qrqGXISW6aeMZ&t=20m

FWIW : I would also suggest a Hunter 4x4 wheel alignment. After I had mine done at GlenRands it was like driving a different vehicle.

Glenrands are a lot more expensive than a standard tyre fitter for a Hunter 4 wheel alignment but they will persevere until it’s right which is worth it. I paid around £270 a couple of years back. No point having it done IME unless all your suspension joints and bushings are tested and free of movement or wear. 2012 TDV8 Vogue (L322)

Cheers JG, I did my rear suspension bushes earlier in the year, not done the fronts yet, maybe if I replace those I will go for the hunter alignment.

Gotts in Alton did my Grenadier. Digital machine so had a print out of before and after. Adjusted the suspension caster as well. Was the right side of £200. Glenrands are fairly local to me and I need a few other bits doing so will be making my way there at some point. 2012 Westminster Aintree/Ivory 4.4TDV8