Replaced the nasty old piston ring on the WABCO air suspension pump with a $14 kit off ebay.
Hopefully this will eliminate my accumulator requests filling errors on the system.
Here is what a 110,000 mile WABCO piston ring looks like.
The outer surface of the ring was severely pitting.
The cylinder bore had scratches in it so I touched them up with a little fine sandpaper to knock down some of the fine ridges that the old ring had worn into the bore.
Will see if this solves the issue and for how long
Update: took a short ride this evening for groceries and gas and the "Self Level Suspension Inactive" code did not appear during the drive. For now the new piston ring appears to have been the solution. (fingers crossed that this continues to be the case
)
Update 2/17/2018: after about 400 miles of driving, the air suspension code remains OFF and the air suspension continues to function normally.
Mike