Car wouldn't turn on on a snowy night. I tried to jump start it and the car turned on and off a few times on its own while the brake pedal sprung back. Something didn't feel right so I shut off the car immediately. I decided to come back in the morning to try again. When I got in the car, I noticed the car had power due to a light on the dash with no key in. So I powered on the car to find the red triangle and check engine light on. I checked the 12v battery using the info and headlight trick, and it shows 9.4v. This could explain the red triangle and check engine light. My question is can I use my portable jump starter to jump the battery to 12v? Perhaps the first jump had some kind of problem due to the cold or snow. What kind of potential problems am I looking at? Thanks.
HIGHLY likely that it did NOT "fix" the actual problem........but just bypassed it for a short period. You need to find out why it was that low in the first place. A total discharge like that is hard on a battery, regardless of what actually caused it, so you might need a new battery too. And the main connections and charging voltage should be checked too.
