RV steps don't retract when engine is started

I just got my rig out of the shop for some maintenance, and on my way home (almost all the way home), I noticed that the steps were not retracted. I drove 25 miles on the highway without seeing that - that's on me.

The steps have 2 modes - (1) auto open and close whenever the screen door opens and closes; and (2) stay open ignoring the door opening or closing. But when in this mode, starting the engine causes the steps to retract. At least they USED TO work that way.

Starting the engine no longer causes them to retract when in mode 2. So mode 1 works as it always has, but mode 2 only partially works. The steps stay open no matter what.

I've had the rig 6 years, and this is the first time I've seen this behavior. I'm pretty sure they worked properly when I dropped the RV off at the shop (2 months ago!), I almost always have the steps set to mode 2, and I think I remember the steps sliding out when I arrived at the shop to drop it off. But to be honest I can't swear to that.

When I picked it up, the door was closed and the steps were out, so it was definitely in mode 2. They just didn't close when I started the engine and drove away.

Anyone ever see this type of behavior, or can hazard a guess as to what might be causing this problem?

Thanks!