d04f9e2c_r__The_Last_Airbender_resource__Aang_s_experience
[Chakra] Water Chakra [Deals with] Pleasure [Blocked by] Guilt [Location] Sacrum [Aang's experience] 
When asked what he blamed himself for, Aang reminisced of the day he fled the Southern Air Temple upon finding out that he was the Avatar. On top of this, he remembered the time that he hurt Earth Kingdom soldiers at General Fong's fortress while in the Avatar State. Pathik told Aang to accept that these things happened and urged him to prevent them from clouding his judgment and poison his energy; he stated that Aang must forgive himself if he wanted to be a positive influence on the world. Aang did so and successfully opened the second chakra.
Chakras - Avatar Wiki, the Avatar: The Last Airbender resource
Aang's experience