Heat a grill to medium-high heat. Add the corn and jalapeno to a sheet tray, drizzle with the olive oil and sprinkle with salt and pepper. Grill on all sides until lightly charred, about 6 minutes total. Remove from the grill and cool for a few minutes until you can handle.
Use your knife to remove the corn kernels from the ears of corn. Finely chop the jalapeno. Add both to a bowl, and then stir in the tomatoes, avocado, red onion and lime juice. Taste for seasoning and adjust as necessary with more salt as needed. Serve with tortilla chips.