As with any warning lights, the best course of action is to get an ODBII reader and LeafSpy so you can pull the underlying codes, understand the problem, and possibly clear them. When you get the codes, post your codes in this thread and someone may be able to help you.
I use the BAFX reader and it's worked very well for me: https://bafxpro.com/products/obdreader
I have my reader plugged into a right-angle extension cable (as described in the Wiki). I resoldered pin 16 to pin 8, so that the adapter is only on when the car is turned on. This isn't strictly necessary, but it avoids power draw from the battery when the car is off, since I intend to never unplug the reader.
You should also charge the 12V battery (under the hood) with an external charger when the car is off. Then check the voltage. If the voltage is low, replace the 12V battery (a common cause of unexpected codes)