I would have expected the update to clear the code.
There are a couple causes of the MIL, some are legit, the rest are either software or software workarounds for flaky sensors--for example bogus evap sensors.
Generally if the MIL light is on solid, it may go away after a few start/stop cycles.
If it is flashing, best to use a code reader to see why or get it to a repair shop.
Mine did this twice in the first few hundred miles and hasn't done it since with over
10K on it now--although we did tighten up the ground bolt which is part of current the recall.
Check out Milous' WK2Jeeps.com - 2011-2016 Jeep Grand Cherokee