AIR. SUSP. INACTIVE/HDC INACTIVE

[invisible]

I drove off from a parking lot for about 30 seconds and at the exit comes audible sound and the message AIR. SUSP. INACTIVE and HDC INACTIVE with yellow exclamation mark on dashboards.

Ignition on/off, driving for 30 min off, then on - did not help. So it has been like that for last couple of days.

I replaced front struts (shipped from Island 4x4) and height sensors just two months ago ($2700 spent on it).

What can I do to troubleshoot the problem and resolve it? Fuzes, etc? Else?

I also have ALL COMMS III cable with software and just got used/replacement BCU from Ebay. Should I try to swap the BCU (disconnect battery first), reset settings of BCU after connection and see if it fixes the problem?

If not, what else? Looking for collective wisdom here.

P.S. 2005 RR HSE. Bought for $7500 2 years ago. Spent $10K on repairs.
P.P.S. The most exensive car is a cheap British car....

 

[alldazed]

can you access any codes ? If it’s not losing air it could be the compressor which you should be able to hear when it’s working.

 

[invisible]

All COMMS III showed probem with left front height sensor. I cleared codes and it does not come back but message remains.
How do I check compressor considering that I can't switch into offroad/HDC mode? Once I turn off and take key off the height changes in 1-2 min.

 

[alldazed]

Assuming it keeps height you can probably assume compressor is working, I usually hear mine faintly though after loading up with people or load. I found the below in the archives which may relate to you re the code you got for the height sensor.

Anyone ever encounter the Air Suspension Inactive fault where back left tire progressively gets much higher than the other 3? If so, what was the solution?

There is no error code on my 2003 RR. All the air bags are less than 1 years old and no leaks.

Had this on my 2007 rrs and found the wheel height sensor was really tight, i soaked it with wd40 around the pivot and freed it up also the end link to the top wishbone may have rusted and needs cleaning so it can move

 

[invisible]

Thanks for insights.

Just to recap:
1. Front air springs and all 4 height sensors were replaced 2 months ago
2. Only suspencion and HDC inactive messages are coming. There is no message about limiting max speed
3. I checked fuse #57 in the glovebox, it is fine. Checked (visually, without uplugging) relay in the trunk responsible for the air suspencion, also no signs
4. Looked at the height sensors in front and checked cable connection - seems fine
5. We live in semi-desert area - there was no rain in last 2 months, so there is no possibility that water got it
6. Battery is fully charged

So.. what next?