i have a 2004 l322 that both front air bags wont fill and is sitting on bump stops. i replaced both front air struts and still bags wont fill. no sound from compressor and its giving no codes. i have checked fuse and replaced relay. tried turning wheel from stop to stop and still nothing. is there a way to test my compressor. also scanner im using is a snap on modis utra and when i try to enter under air suspension it just say no communication.