I had the same thing happen to me, never did try and reset the ECU though. I believe someone else had this problem in another thread, the dealership replaced the steering wheel switch to fix it. I'm about to go through the same process so I will share my research:
Here's the other thread:
Cruise "SET" light flashing
Find out if it is actually the switch, there is a troubleshooting tree in the engine control service manual that you can use a voltmeter on. You have to register to d/l.
Pulling the wheel and installing a new switch. This thread is actually for installing new switches, but it should be the same
You will need part #4 from this page:
Hope this helps, post if you fix it before I do, I hope this is the solution. I also heard some talk about cleaning the contacts on the switch, but it seems like a lot of work to get to those contacts.