Allroad ride-height problem

[alanadams]

I've got an intermittent problem with the ride-height system. Occasionally the dashboard indicator comes on steady, and the manual controls are disabled. Switching off the ignition resets it, for a while.

I can sometimes cause this event as follows:

Put a 50kilo load in the boot.
With the engine running, starting with the ride height on low, manual or auto setting, press the up button.
After between one and a half and two minutes the indicator will come on. If it doesn't, press UP again and it is likely to show the fault.

It does this even while parked. Once it has happened, it occurs every time the height is increased. Driving around and trying again may not show the problem.

At other times, it will change height correctly, although it takes 30 to 60 seconds per step, and always moves the back of the car up first. Going down takes about 20 seconds per step. I saw a review somewhere which said it changed in 3 seconds - can anyone confirm this?

With the load in the boot, driving over bumpy roads and speed bumps doesn't trigger the fault, at any ride height.

With a bigger load in the car, say 300 kilos, it will drive for perhaps 20 miles then put the indicator on.

In thinking low air pressure, leaking control valve, leaking pipe (latter unlikely). Any thoughts?

Is the compressor electric or engine driven?

 

[waddecar]

I haven't timed changes on my 2001 module but 20-30 secs seems about right. Level light blinks whilst change is in process.
Haven't noticed a 'rear first' tendency.
Would worthwhile connecting up a VAG COM
May be worthwhile searching the audiworld allroad forum

 

[alanadams]

More info.
I tried putting some weight into the back. Changing ride height upwards took between one and two minutes per step. If it was over around 90 seconds, the error light came on. Switching ignition off cleared the error. Repeatable several times.
Took the load out - no errors. Drove home. Tried to repeat it - no errors.

Now I have VAG-COM. It shows two errors on the level control module
01772 - signal from level control pressure sensor 27-10 implausible signal, intermittent
and
01316 - 79-10 - shareware version please register - intermittent.

Can anyone throw any light on the second one?

I also have one error in the ABS system
18265 -load signal:error message from ECU P1857 - 35-10 - - - intermittent.
Should I worry about that one?

 

[alanadams]

I've managed to watch the system with Vag-Com while it was giving trouble.
The fault showed up for the first time with no extra load in the car. A possible link - last week it had four new tyres fitted, so it was jacked up (in jacking mode) and all four suspension legs dropped to maximum extension.

Vag-com showed that the front height sensors had no change when the system was asked to go up. The readinga started out as 120, 97, 123, 129 units extension in the order front1, front2, read1, rear2. After a while it had settled at 120, 96, 140, 146. At this point the dashboard error light came on and fault was recorded as
01400 - Suspension level control
11-10 Control level not reached - intermittent. Clearing the DTC also turned the dashboard light off.
The suspension did appear to have moved the car up at all four corners.
After several repeated attempts the car and the Vag-Com readings did move up on request, and I ran it up all four steps successfully, and down again.
Does this point to one or both of the front ride-height sensors being faulty. (Which is "front 2), as that seems to have a significantly different reading all the time?)
Incidentally I have thought for a while that the self-levelling headlights were set too high - is this linked?
How much recalibration is needed after replacing sensors?