No power whatsoever

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Sounds like your small 12v battery discharged, a common occurrence on the FFE.
You need a 12v car battery external charger, I always keep one in my garage for emergencies.
 
nobleisrael said:
Does the 12v battery charge when plugged into shore power?
:lol: "shore power" Either your 12V battery has reached the end of it's life, you left something on, or a module is misbehaving and didn't turn off draining the 12V battery.

When plugged into an EVSE and the high voltage battery is charging the 12V battery gets some juice too. When the car is on, the DC-DC converter performs the identical function of an alternator on an ICE car (providing power to the 12V system and keeping the 12V battery topped off).
 
If the 12v battery is drained completely, how long does it take for the 120v evse to charge the 12v enough for the car to start?
 
spirilis said:
Main question is, if the 12V battery is dead, can the car charge at all?
Absolutely not. The circuit that operates the charge port operates on 12V. A dead 12V requires a regular automotive 12V charger or jumpstart from another battery or car. Once the car is started or the onboard charger has started charging it turns on the DC-DC converter to also charge up the 12V and supply power for cooling pumps etc.
 
Carbuff said:
If the 12v battery is drained completely, how long does it take for the 120v evse to charge the 12v enough for the car to start?
Infinity. Any EVSE won't charge a dead 12V battery. The EVSE is just a "smart" extension cord that tells the onboard charger how much current it can draw. You need the 12v battery to power the circuitry that initializes the onboard charger and DC-DC converter. What you need is a jumpstart or a standard 12V battery charger.
 
Seems counter intuitive that the 12V battery won't charge even if the high voltage battery is fully charged. But that is absolutely 100% true, no power goes to the 12V battery unless there is some energy there already.

You can kind of see this for yourself - when you connect a jump starter or battery charger, you can hear some relays start to click as the battery gets enough juice. Those relays are the thing that allows the whole car to work, and oddly, the charger to start charging the 12V battery.
 
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