diff --git a/lms/djangoapps/instructor/tests/test_api.py b/lms/djangoapps/instructor/tests/test_api.py
index 0158ce0ec8c6..0cb7e009454e 100644
--- a/lms/djangoapps/instructor/tests/test_api.py
+++ b/lms/djangoapps/instructor/tests/test_api.py
@@ -713,7 +713,7 @@ def test_bad_file_upload_type(self):
         """
         Try uploading some non-CSV file and verify that it is rejected
         """
-        uploaded_file = SimpleUploadedFile("temp.csv", io.BytesIO(b"some initial binary data: \x00\x01").read())
+        uploaded_file = SimpleUploadedFile("temp.csv", io.BytesIO(b"some initial binary data: \xC3\x01").read())
         response = self.client.post(self.url, {'students_list': uploaded_file})
         assert response.status_code == 200
         data = json.loads(response.content.decode('utf-8'))
diff --git a/lms/djangoapps/instructor/tests/test_certificates.py b/lms/djangoapps/instructor/tests/test_certificates.py
index 9921ae6d6831..ce3433f312d8 100644
--- a/lms/djangoapps/instructor/tests/test_certificates.py
+++ b/lms/djangoapps/instructor/tests/test_certificates.py
@@ -888,7 +888,7 @@ def test_bad_file_upload_type(self):
         """
         Try uploading CSV file with invalid binary data and verify that it is rejected
         """
-        uploaded_file = SimpleUploadedFile("temp.csv", io.BytesIO(b"some initial binary data: \x00\x01").read())
+        uploaded_file = SimpleUploadedFile("temp.csv", io.BytesIO(b"some initial binary data: \xC3\x01").read())
         response = self.client.post(self.url, {'students_list': uploaded_file})
         assert response.status_code == 200
         data = json.loads(response.content.decode('utf-8'))