diff --git a/rosidl_adapter/rosidl_adapter/action/__init__.py b/rosidl_adapter/rosidl_adapter/action/__init__.py
index 6e8719b6c..cb7a74b83 100644
--- a/rosidl_adapter/rosidl_adapter/action/__init__.py
+++ b/rosidl_adapter/rosidl_adapter/action/__init__.py
@@ -24,7 +24,7 @@ def convert_action_to_idl(package_dir, package_name, input_file, output_dir):
     abs_input_file = package_dir / input_file
     print(f'Reading input file: {abs_input_file}')
     abs_input_file = package_dir / input_file
-    content = abs_input_file.read_text(encoding='utf-8')
+    content = abs_input_file.read_text(encoding='iso-8859-1')
     action = parse_action_string(package_name, input_file.stem, content)
 
     output_file = output_dir / input_file.with_suffix('.idl').name
diff --git a/rosidl_adapter/rosidl_adapter/msg/__init__.py b/rosidl_adapter/rosidl_adapter/msg/__init__.py
index b02b7b5bd..14d961957 100644
--- a/rosidl_adapter/rosidl_adapter/msg/__init__.py
+++ b/rosidl_adapter/rosidl_adapter/msg/__init__.py
@@ -24,7 +24,7 @@ def convert_msg_to_idl(package_dir, package_name, input_file, output_dir):
     abs_input_file = package_dir / input_file
     print(f'Reading input file: {abs_input_file}')
     abs_input_file = package_dir / input_file
-    content = abs_input_file.read_text(encoding='utf-8')
+    content = abs_input_file.read_text(encoding='iso-8859-1')
     msg = parse_message_string(package_name, input_file.stem, content)
 
     output_file = output_dir / input_file.with_suffix('.idl').name
diff --git a/rosidl_adapter/rosidl_adapter/srv/__init__.py b/rosidl_adapter/rosidl_adapter/srv/__init__.py
index c57b7013f..f3abe87f8 100644
--- a/rosidl_adapter/rosidl_adapter/srv/__init__.py
+++ b/rosidl_adapter/rosidl_adapter/srv/__init__.py
@@ -24,7 +24,7 @@ def convert_srv_to_idl(package_dir, package_name, input_file, output_dir):
     abs_input_file = package_dir / input_file
     print(f'Reading input file: {abs_input_file}')
     abs_input_file = package_dir / input_file
-    content = abs_input_file.read_text(encoding='utf-8')
+    content = abs_input_file.read_text(encoding='iso-8859-1')
     srv = parse_service_string(package_name, input_file.stem, content)
 
     output_file = output_dir / input_file.with_suffix('.idl').name