when car starts a red warning triangle comes on with an airbag icon. it operates

The triangle is you main eclectic battery that runs your engine and gives you good gas mileage. You can fix it your self if you mechanical by replacing bad cells it might cost 40-50. You can buy rebuilt batteries for 1500 or so. Dealer can do a new one for 3000.00- 3500.00. I replaced the one bad cell in mine works great now. It is a lot of work. Only spent 35.00.