I would expect an alarm to sound and even a camera in the car to catch the action even with a flat 12v battery.

 

 

 

 

 

 

3 minutes ago, toot said:

I would expect an alarm to sound and even a camera in the car to catch the action even with a flat 12v battery.

Where would the camera in the car get power when the low-voltage battery is flat? Same for alarm. It's the same for all cars.

 

Only difference is, Tesla door handle is electronically operated and there's no physical key. So when low voltage battery is flat, need another way to re-gain access: go through the frunk to low voltage battery and then jump the low voltage battery to close contactors for HV battery. Then you can use keycard or phone key to unlock as normal.

 

When low-voltage battery isn't flat, operating normally, jumping the front bumper connectors will not do anything. There is no security risk.

 

 

 

On related note, latest Tesla's no longer have lead acid batteries. My one comes with a 16v li-on low voltage battery that is supposed to last life of the vehicle. So unless HV battery is completely drained or car was in an accident, chance of needing to do this front bumper trick as owner is 0.

Well in cars / Skoda the Alarm Siren has it's own battery. 

 

Surely a mobile battery like a Tesla / EV (a battery on wheels) is with lots of energy but just a flat 12 v battery can have a bit of power for the security, CCTV?

 

Maybe designing a car that makes Fart noises is more important than protecting stuff in the frunk.

 

 

Edited 6 June, 20233 yr by toot

The HV battery is only connected after safety checks and contactors require power from low voltage battery to close. The HV battery is completely disconnected when the car sleeps/turned off. Whereas the alarm system is still on low-voltage system so that it can work when the car sleeps/turned off. This is the same for all EV's.

 

Are you sure about alarm going off with flat battery? When I had a flat battery in my Octavia, the alarm only went off after connecting jumper cables, giving power to the car.

 

Again, during normal operating, and with latest cars having vehicle lifetime li-on low voltage battery, the jump trick on the tow eye wouldn't open the frunk. It's not a security concern.

As long as having charge keeps a relay open which means those leads only work when everything is dead…