When the headlight (light switch in the headlight or AUTO position) is on and all doors (and tailgate) are locked and closed, the position light and headlight will come on for 15 seconds if any of the below is performed.
At this time, if you press the door lock or unlock button, the position light and headlight will turn off immediately.
Kia Niro 2017 (DE HEV) Service Manual: AC Inverter Unit Repair procedures
Removal
1.
Disconnect the negative (-) battery terminal.
2.
Remove the luggage side trim [RH].
(Refer to Body - "Luggage Side Trim")
3.
Disconnect the AC inverter unit connector (A).
...
Kia Niro 2017 (DE HEV) Service Manual: High voltage battery handling guide
High voltage battery system
inspection guide
Be sure to read and follow the “General Safety Information and
Caution” before doing any work related with the high volt ...