Air suspension going crazy
 

Hi guys, I am having problems with my EHC II, I have an x5 4.4 model 2003.
A while ago I got a self level susp inactive. Took it to my specialist and reset the fault it worked fine, then I noticed that I wasn't able anymore to control the system manually from the command on the dashboard. If I give a command to lower the vehicle the rear goes down but the front go up and stay up no matter what different command I give. It's not at all in sync. I suspected the EHC unit but after replacing it and rein coding a new one the problem still persist. It ended up not being the EHC unit. Im suspecting its the battery ( since when we plug the gt1 the power supply is lower then 13 amps, so we had to plug the charger ). I need your help guys, I'm really getting very frustrated with this issue.