12 v battery usage

Chrisjk

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Hi
sorry if this has been asked before - couldn't see it anywhere
Is there a definitive list of all the things that draw power only from the 12 v battery?
 
I don't think there's anything that qualifies.
All the 12V stuff can be powered from the DC-DC converter and will be when in Ready mode.
 
Thanks, but does that mean that the 12v battery is only needed to power the door locks? i am sure i have had the radio on without the Ready mode. I must check if other things work in that condition too. you have set me thinking
 
Thanks, but does that mean that the 12v battery is only needed to power the door locks? i am sure i have had the radio on without the Ready mode. I must check if other things work in that condition too. you have set me thinking
No, various other things are run from the 12v battery. Heated seats, lights, media unit and more. I don't have a comprehensive list though, sorry.
 
This is only my opinion on this subject.
Anything that you would normally find powered by the 12 volt battery on a ICE car.
Lights / wipers / heater fan motor etc will be powered in the same way on the ZS EV.
The heat provided to the cabin is powered via the HV traction battery.
There is no way you could power the cabin heater element, via a 12 volt battery.
It would be flat in minutes !.
Charging the 12 volt battery from the HV battery ( maybe via the inverter ) can only be achieved if the car is in the READY mode.
The 12 volt battery is then receiving a charge of around 14.5 volts.
As it would in a ICE car, but via the alternator of course.
 
The 12v battery is exactly the same as in an ice vehicle, it is a starter battery for starting the vehicle and to use in an emergency situation powering the necessary systems (lights, hazard lights etc). If you are parked up using the radio, lights etc they will be drawing power directly from the 12v battery unless you have the car switched fully on (traction battery on). With the traction battery on all the 12v electrics run from this vier a Dc to Dc converter so no worries about discharging the 12v battery, this system also charges the 12v battery. Best practice is to treat the 12v as a starter battery then you will never have any issues aside from cell or age related failure.
 
…..apart from the higher voltage traction pack that powers the motor, connected electronics and heater element all the other electrical components are 12v.
I will include an image of the orange high voltage cables that feed the heater element in a Tesla model 3 - It will be something very similar in the ZS EV.
As @Alansurfer correctly points out, the heater blow motor ( fan ) is powered by the 12 volt battery.

Tesla HV heater wiring 2021-06-24 at 21.09.38.png
 
The list will be pretty similar to a conventional ICE car. it would be brought across more or less from the petrol zs. No point re inventing the wheel. I think the 12v battery will have fewer cca (not looked into it) as it won’t have to power a starter motor from dead cold.
 
Check the fuses section of your manual - this is pretty much a definitive list of the 12V appliances.
 
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