It’s -9f and my [battery](/topics-battery-dodge/) light c...

Hi and welcome to JustAnswer! You can ask unlimited questions to any of the 12,000 Experts! From doctors, lawyers, tech support, contractors, tutors, auto and boat mechanics, appliance technicians, veterinarians, accountants, appraisers, psychologists, engineers, heavy machinery masters, dream interpreters, and more, we've got you covered, 24/7. My name is \*\*\*\*\* \*\*\*\*\* I will be able to assist you. I’m sorry that you’re having trouble with your vehicle. Don’t worry though, we’ll be able to figure this out. Thank you for taking the time to let us help you out with this problem and hopefully we can sort it out quickly. Please understand that I do not know your knowledge or capabilities so I may need to ask questions to find out basic information to help solve your specific problem. Sometimes it may take a moment for me to respond because I may have to look up information about your concern. I appreciate your patience and will provide responses as soon as possible. If the battery warning light came on with the engine running then the alternator is most likely bad. It's possible that the battery is faulty so I would have it tested but typically this will be caused by a faulty alternator. The system should have at least 13 volts with the engine running. IF the light is on without the engine running then your battery is discharged and will need to be recharged and tested. My goal is to give you the best service possible and to help you. If you have any questions or concerns, please don’t hesitate to let me know. If I’m not online at the time, I will respond ASAP when I get back.

Is this common in sever cold weather?SevereIt’s negative 9 outside

Yes. Cold weather always affects electrical components. If possible I would recommend to park the vehicle in a heated garage.

The car transmission temp has warmed up 80F

Is the battery light on with the engine running?

Should I turn off the car and restart?

No I was just wondering if it was running. Your alternator is most likely bad. Check the voltage with a voltmeter. It should show at least 13 volts.

This the first time this has occurred. At what trans temperature should it be considered warm enough to shut off?

You can shut it off at any temperature.