Tesla Model 3 - How to Replace 12V Battery

[@eb1888.]

Do not reconnect the high voltage disconnect under the seat until you have reconnected the new battery. If you're going to do it the way you did, there's no reason to use the disconnect for safety.

[@MTNRanger]

This is what that Tesla instructions tell you do. service.tesla.com/docs/Public/diy/model3/en_us/GUID-2588F809-41E3-43F1-84E5-6745C7C18DBE.html

[@AdrienneWhelan-r6w]

​@MTNRanger Tesla does say to do that... but why? You disconnect the HV to make "safe". You then disconnect the positive. You then put the battery back in. Connect the HV... and go working on the positive?? I don't get it. What's the point of disconnect the HV if you plug it back in before you connect the battery

[@IIMAVII]

​@@AdrienneWhelan-r6wI also thought that it was utterly bizarre to reconnect the HV lead first before reconnecting the positive lead on the new battery. Surely the reason for disconnecting the HV lead in the first place is for safety. Good video to be fair and well explained but that reconnection of the HV lead seems a bit odd, even more odd seeing as that's how Tesla tells you to do it.

[@andrewsjra]

Can you please make a video showing how to check the status of the 12V battery in service mode? Both my wife’s and my Model 3’s didn’t receive the error message you did until the battery was dead. Had to get Tesla tow the car to the service center to replace it back in 2020.

[@MTNRanger]

I went into the service mode and the error messages are the same as what was displayed on the main screen. Do you need instructions for service mode?

[@myyoutubechannel1509]

Also coat the terminals with petroleum jelly to prevent corrosion

[@MTNRanger]

The 12 V batteries don't live long enough to get rust. I don't remember any cars of mine in the last twenty + years that had corrosion on the terminals.

[@Junior-w1v4f]

Where are you located because every where I look those batteries are $250.00 and up

[@MTNRanger]

Tesla Service sells them for $85. I'm in Raleigh, NC.

[@eddisonreyes9061]

It doesn’t matter if you touch the body of the car when you’re doing the negative or neutral side neutral is ground.

[@MTNRanger]

Yes, I still like to keep it out of the way.