L322 Air Suspension Inactive / HDC - gurus needed, can you help?

I know this is a common fault that has been discussed many times on this forum, so apologies in advance, but really hoping for some clarity!?

The ‘Air suspension not active’ fault has come up in the past, but only now and then and would clear, however now it is all the time, along with HDC fault too.

Summary of what I have done so far:
Cleared the codes using iCarsoft which will clear the message on dash, the suspension ride height change works fine and pretty quick, but then I drive for a few mins and it the 'Air Suspension Inactive' pops up again. When I clear the codes it shows in 3 main areas, so the system must be linked:

‘Air suspension’ (Code 32 no Canbus),
‘Steering angle sensor’ (temporary inactive fault)
‘ABS’ (no signal or no data)

I clear these three areas and all is good and dash clears. After I drive for a few minutes, the ‘Air Suspension inactive fault’ comes on dash I also usually get the HDC error too. Sometimes I can clear the error by doing the steering wheel calibration method, (full right light to left lock), sometimes I need to use the iCarsoft.

Things done so far:
I have checked and cleaned the connector plug to the rear air compressor, checking for water ingress, all seemed fine and dry.
I have stripped down the air compressor and replaced piston ring, (some slight signs of wear)
I have checked the plug and dampness to the ECU control module for air compressor in the front right footwell.
I have checked for loose connections to the Steering Angle sensor.

When the ‘Air suspension inactive fault’ comes on the dash, it almost seems to be when I go over a bump, or when I engage reverse sometimes, but not all the time.

My gut feeling is perhaps the steering angle sensor is worn, when I check on the diagnostics, it seems to behave fine with good angles though? May have worn contacts?

P.S. Could it be a ride height sensor?

Any help would be very appreciated.

My thoughts would be the steering angle sensor fault shutting down the abs module and breaking down the canbus if not then
Id be looking at an abs module myself,
One i have noticed along the way is that there is a lower column angle sensor on the shaft and also the ring gear just behind the steering wheel measures the angle too,

If your steering wheel is 30° off center too the lower sensor it will throw the abs limp mode on too

stustrong said:

My thoughts would be the steering angle sensor fault shutting down the abs module and breaking down the canbus if not then
Id be looking at an abs module myself,
One i have noticed along the way is that there is a lower column angle sensor on the shaft and also the ring gear just behind the steering wheel measures the angle too,

If your steering wheel is 30° off center too the lower sensor it will throw the abs limp mode on too

Click to expand...

Thanks for the reply, my thoughts are the angle sensor too, as the pump works well, the car does not sag, and ABS values on each corner look consistent. Now I can see and touch the angle sensor, but how hard are they to remove/ replace, I did find a good post on this forum to follow. Also If I buy a new steering angle sensor, I believe they need to be coded to the car? Can the contacts be cleaned perhaps?

Not coded just callibrated and its a strip down of the column, im sure its top half you need away it, be it a bit or remove a lot depending if you want to work on your back or knees the teethed section slides through the center of the steering angle sensor, iv never had any issues apart from sitting my wheel off center and upsetting everything changing a lower steering knuckle so i cant help anymore im afraid,

Hi mate as the guys have said steering angle sensor fault or off center will send air suspension into a fit of rage as your code reader said inactive