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So I went to start my car this morning. It ran for about 1 seconds and died. Voltage reads 12.6. the horn/ alarm started beeping. Went to disconnect batt it stopped but when I reconnected it just started back. I removed fuse and I'm not sure if that's why the headlights flash for a 1 second on ,one second off interval or the electrical system is freaking out because of the fuse. I was reading that fuse can affect other lights as well. I hope and pray it's just the batter and not something more expensive but the fact that V reads 12.6 is worrisome.

Also about 2 years ago I replaced the electrolyte in the batter instead of replacing it. The was about 2 batteries ago so the one that's currently installed is stock and is actually a sealed batt. When I replaced the electrolyte about 2 years ago I think it over charged somehow because the battery overflowed. When I found out I sprayed with baking soda to neutralize. About 2 months after that incident all my emergency lights started going off. They stay on for a while then off. It's totally random. When they are on I don't have my brake hold feature so it kinda sucks. Iver reset the computer multiple times but it just seems to always come back. Sometimes I notice it will start back again after a rain or a carwash but this might be speculation. A mechanic said it has something to do with the radar on the front quarter pnl but I doubt it. Any input would be greatly appreciated as atm my car is immobilized and I have no way of getting underneath it

 
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year and model, please...

 
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my apologies, 2019 Honda civic sport 1.5 T

 
Rep Power: 243

Is the battery original? Low battery voltage can make cars do weird things.