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High Voltage Cutoff Switch - When and How To Use Properly?

5.8K views 1 reply 2 participants last post by  Ixlr8  
#1 ·
There hasn't been a post on the HV cutoff switch that I can find since March 2022, and then I could only find one. I'm a January 2023 owner and would appreciate clarification on:
1. How to pull out (up? down?) the yellow tab. The Owner's Manual (page 1-75) says to do that in an accident or other emergency.
2. What are other cases when it should also be temporarily removed? I recall some 12v battery issue posts that talked about resetting the car that mentioned this cutoff switch in addition to waiting 15 minutes for discharge before using a jumper battery (besides the March and April 2023 posts about Bluelink pinging limits and TSBs addressing 12v battery and charging interruption issues.)
3. What about reinsertion? Anything to do or watch for before doing that if you're just trying to reset the vehicle due to a 12v battery or similar problem?

I and I'm sure other newer owners would appreciate a review of when the HV batteries should be disabled with temporary removal of the yellow tab. Thanks.
 
#2 ·
There hasn't been a post on the HV cutoff switch that I can find since March 2022, and then I could only find one. I'm a January 2023 owner and would appreciate clarification on:
1. How to pull out (up? down?) the yellow tab. The Owner's Manual (page 1-75) says to do that in an accident or other emergency.
2. What are other cases when it should also be temporarily removed? I recall some 12v battery issue posts that talked about resetting the car that mentioned this cutoff switch in addition to waiting 15 minutes for discharge before using a jumper battery (besides the March and April 2023 posts about Bluelink pinging limits and TSBs addressing 12v battery and charging interruption issues.)
3. What about reinsertion? Anything to do or watch for before doing that if you're just trying to reset the vehicle due to a 12v battery or similar problem?

I and I'm sure other newer owners would appreciate a review of when the HV batteries should be disabled with temporary removal of the yellow tab. Thanks.
The attached document from Hyundai may add some insight and answer some of your questions.

I am also linking a YouTube video for replacing 12v where installer actually pulls on the HV fuse tab and why.

12v battery replacement process
 

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