What does the Jeep Liberty DO NOT DRIVE light mean?

I got this email from my daughter.

So, earlier this week, I notice that I am past due for an oil change,
about 3 months and 3,000 miles late! Believe it or not, I'm usually
timely with these things, but it was due right after the move, and I
was caught up in all of that activity!

So, with plans to get it done this morning, last night, leaving work,
the oil pressure warning light comes on. I start driving home, and at
a red light, check the manual to see it says "DO NOT DRIVE" when this
light is on. I pull into the Rite Aid. Power engine down, power back
on, and the light isn't on. So I continue on home.

This a.m., start her up, and the light is on. So, I did the same as
last night, drove until it was warm, then shut her down and started
her back up. No light. Good.

I make my way to a Lube Stop afterwards and they got me right in. Oil
was a little low, and there was major sludge build-up. So, I got it
cleaned out, oil change, air filter change (I know, I know, it's a
waste of money right, but I always fall for it nonetheless!), fluids
topped off (coolant was a little low).

Was the DO NOT DRIVE light related to the badly needed oil change?

 

Indirectly -- it was directly related to the low oil pressure which
meant that (unless you're exceptionally lucky) all the driving you did
with the oil pressure low was chewing up the bearings in the engine.

How low was a "little" low? Major sludge buildup with a single
3000-mile late oil change seems very unlikely...

 

I agree with Joe, Pete.

You need to instruct your daughter that that particular light doesn't
mean stop if you'd like to. It means stop now and don't run the engine
until enough oil is put in, and also find out if there's a reason it is
low other than just gradual loss over time.