Check engine light P1EE6

DTC P1EE6 basically means the on-board charger was not detecting AC voltage present when charging conditions indicate is should.
The most likely causes are a blown 20A fuse inside the charge port itself (there's one on each AC leg) a bad AC connection at the charge port pigtail OR connection at the charger itself. Less likely is an on-board charger issue

However IF a 20A charge port internal fuse is blown, then the question arises why did it blow?
Typically this would be due to internal issues (AC shorting) within the on-board charger itself.

Was this vehicle ever involved in a frontal collision??

HTH
WOT

Jim Fallston Md. said:

Anytime a check engine light comes on and stays on for any type of code the Volt will not charge for safety reasons according to Chevrolet.

Click to expand...

Not really true actually.
It depends on the actual DTC. Some may have shutting down on-board charging as a fail safe but many do not.
WOT