Hi there,
I have been troubleshooting an issue with my air suspension not working properly on my 2005 VDP with 117k miles.

The car would not level and would ride low, sometimes giving the vehicle too low error or air suspension fault but not always.
I have changed the air compressor.
I can manually run the air compressor by removing the relay and jumpering 12V to it. It runs and fills the reservoir.
If I disconnect the lower connector (solenoid control from ASU) from the solenoid unit in the trunk, I can manually actuate each of the 4 solenoids and lift each corner of the car, however, to do this I need to have the compressor jumpered on as the ASU will not command the compressor to start even when the reservoir runs out of pressure.
If I reconnect the the ASU connector and replug the compressor relay (all back to normal) the ASU will open the bleed valve on the solenoid bank until the car is too low again.

I finally got the JLR SDD working and received an error trying to communicate with the Wabco ASU, the software just shows a red X for the ASU module and when I try and run a calibration or tell it to run the air pump I just get a comm error.

Does this mean I need a new Wabco ASU?

Any help or suggestions are appreciated.
Thanks
Paul

 

Paul,

I am having the same problem. I have jumped each solonoid to ground and jumped the compressor. Compressor was replaced last week, all solonoids fully functional when jumped, no significant height drop overnight, ASU doesn't seem to kick in and do it's job. I am thinking of making a manual momentary push button dash to manually bypass the ASU.

What did you end up doing? Did replacing the ASU fix it or was it the R7 relay in the rear?

Anyone's input on this topic would be greatly appreciated.


Suzanne

 

Did you try to communicate with the suspension module??
Are there DTCs logged??

bob

 

You could try removing rear seat and check/clean plugs to ASU also check ASU for possible water ingress etc.

 

Hi Suzanne,
In my case I accessed the ASU module behind the rear passenger seat and found it was a broken wire / bad connection to the cars network (CANBus I think) once that was repaired everything seems to be working fine again. I did purchase a used ASU thinking I would have to replace mine so if that ends up being your issue I have one I could part with cheap here.

Hope you find your solution soon, the car rides MUCH better when the air suspension is working properly.
Paul

 

How exactly did you jump your solenoids?
Same issue started happening to me last week. Just replace struts with all new Arnotts. Compressor run even replaced the compressor ring recently as well.
Thanks!