The other day when the temperature outside was in the single digits, I tried to start my 2005 Prius and it wouldn't start and the red triangle with the exclamation point appeared on the dashboard. I tried a couple more times and it started and ran fine. But now whenever I start the car the red triangle appears briefly and then goes away. Could this be a battery issue?
Yes. This is the only warning you get that the car is not happy with the 12 V battery and indicates low 12 V battery voltage. It is the only time the MCL (master caution light) illuminates on startup. Most people never notice it, so good on you!
