Suspension light came on probably as the compressor ran too long and timed out. Cause yet unknown. Likely suspect leaky bag.
The inlet outlet valve at the bags has also been known to leak as they will get debris and rust in them over the years.
When you get the bags aired back up, squirt them with soapy water, just like checking for a leak in a tire, look for bubbles, even tiny ones like caviar size will be a problem overnight. My guess is you will spot it easily.
The compressor also has a drier on it at the intake. I cut one open here a while back and it was soaking wet and full of rust.
It has something to do with the little air intake box mounted on the core support. Seems it is in a bad place and sucks up water.
Fix the bag that is leaking and be sure to check or replace the drier.
I would pull the drier and squirt brake clean into it, then blow through it with an air hose. If a bunch of rust and trash comes out,replace it, or the compressor will be next.
The drier is full of little silica balls, it is a dessicant to remove moisture
Fact is stranger than Fiction