Heat the olive oil in a large pot over medium heat. Add the diced onion and cook for 4 minutes until it softens.
Stir in the minced garlic, cumin, and chili powder. Cook for 1 minute until the spices smell fragrant.
Pour in the low-sodium vegetable broth, then add the rinsed pinto beans, fresh corn kernels, and diced tomatoes with their liquid.
Bring the soup to a gentle boil, then reduce the heat and simmer uncovered for 15 minutes.
Remove the pot from the heat. Stir in the chopped cilantro and lime juice just before serving.
Ladle the soup into bowls and serve with lime wedges on the side.