PLEASE HELP: Battery shows 0%, but it has a full charge
I have a 2016 McLaren 650S and the dash shows that the battery is at 0%. The battery is NOT dead, however; I connected the trickle charger, and it was immediately at 2/3rd full. I left it connected overnight, and the battery is now completely full. But, the dash still shows 0%.
I took apart the frunk and unplugged and plugged back in the 1-pin battery monitoring cable, but nothing changed. I tried to unplug the battery monitoring cable and start the engine. It showed battery fault (because the connector was unplugged), so I shut her down, reconnected the cable and tried again - but it still shows 0%.
I checked the battery terminals with a multimeter and they're at 13.4 volts.
Does anyone have ANY ideas? Thanks!