You would have to go through your return and see where the difference might be.
If you are using TurboTax CD/Download, you can see your T1 and other forms by going into Forms mode. This TurboTax FAQ shows you how to switch to Forms mode: How do I switch between EasyStep and Forms mode in TurboTax CD/Download?
In TurboTax Online you can see a detailed summary of your return in the online edition of TurboTax by following the instructions on this TurboTax FAQ: How can I see a detailed summary of my return in TurboTax Online? You can also see the actual CRA forms that make up your return by saving/printing your return. This TurboTax FAQ tells you how to save/print a copy of your tax return in TurboTax Online: How do I print a copy of my return in TurboTax?