diff --git a/aider/coders/base_coder.py b/aider/coders/base_coder.py
index a2f8fc0cc..19bef991e 100755
--- a/aider/coders/base_coder.py
+++ b/aider/coders/base_coder.py
@@ -167,13 +167,13 @@ class Coder:
             self.find_common_root()
 
         if main_model.use_repo_map and self.repo and self.gpt_prompts.repo_content_prefix:
-            rm_io = io if self.verbose else None
             self.repo_map = RepoMap(
                 map_tokens,
                 self.root,
                 self.main_model,
-                rm_io,
+                io,
                 self.gpt_prompts.repo_content_prefix,
+                self.verbose,
             )
 
             if self.repo_map.use_ctags:
diff --git a/aider/io.py b/aider/io.py
index ff3cab386..f001d63f5 100644
--- a/aider/io.py
+++ b/aider/io.py
@@ -141,7 +141,7 @@ class InputOutput:
                 return f.read()
         except (FileNotFoundError, UnicodeError) as e:
             self.tool_error(str(e))
-            return None
+            return
 
     def get_input(self, root, rel_fnames, addable_rel_fnames, commands):
         if self.pretty:
diff --git a/aider/repomap.py b/aider/repomap.py
index fab94ec27..df739c8f9 100644
--- a/aider/repomap.py
+++ b/aider/repomap.py
@@ -74,8 +74,10 @@ class RepoMap:
         main_model=models.GPT4,
         io=None,
         repo_content_prefix=None,
+        verbose=False,
     ):
         self.io = io
+        self.verbose = verbose
 
         if not root:
             root = os.getcwd()
@@ -130,7 +132,7 @@ class RepoMap:
             files_listing = self.get_ranked_tags_map(chat_files, other_files)
             if files_listing:
                 num_tokens = self.token_count(files_listing)
-                if self.io:
+                if self.verbose:
                     self.io.tool_output(f"ctags map: {num_tokens/1024:.1f} k-tokens")
                 ctags_msg = " with selected ctags info"
                 return files_listing, ctags_msg
@@ -138,7 +140,7 @@ class RepoMap:
         files_listing = self.get_simple_files_map(other_files)
         ctags_msg = ""
         num_tokens = self.token_count(files_listing)
-        if self.io:
+        if self.verbose:
             self.io.tool_output(f"simple map: {num_tokens/1024:.1f} k-tokens")
         if num_tokens < self.max_map_tokens:
             return files_listing, ctags_msg
@@ -198,7 +200,7 @@ class RepoMap:
 
             with tempfile.TemporaryDirectory() as tempdir:
                 hello_py = os.path.join(tempdir, "hello.py")
-                with open(hello_py, "w") as f:
+                with open(hello_py, "w", encoding="utf-8") as f:
                     f.write("def hello():\n    print('Hello, world!')\n")
                 self.run_ctags(hello_py)
         except FileNotFoundError:
@@ -237,10 +239,8 @@ class RepoMap:
         return idents
 
     def get_name_identifiers_uncached(self, fname):
-        try:
-            with open(fname, "r") as f:
-                content = f.read()
-        except UnicodeDecodeError:
+        content = self.io.read_text(fname)
+        if content is None:
             return list()
 
         try:
diff --git a/tests/test_repomap.py b/tests/test_repomap.py
index cba69e2b1..03aa410f8 100644
--- a/tests/test_repomap.py
+++ b/tests/test_repomap.py
@@ -3,6 +3,7 @@ import tempfile
 import unittest
 from unittest.mock import patch
 
+from aider.io import InputOutput
 from aider.repomap import RepoMap
 
 
@@ -21,7 +22,8 @@ class TestRepoMap(unittest.TestCase):
                 with open(os.path.join(temp_dir, file), "w") as f:
                     f.write("")
 
-            repo_map = RepoMap(root=temp_dir)
+            io = InputOutput()
+            repo_map = RepoMap(root=temp_dir, io=io)
             other_files = [os.path.join(temp_dir, file) for file in test_files]
             result = repo_map.get_repo_map([], other_files)
 
@@ -65,7 +67,8 @@ print(my_function(3, 4))
             with open(os.path.join(temp_dir, test_file3), "w") as f:
                 f.write(file_content3)
 
-            repo_map = RepoMap(root=temp_dir)
+            io = InputOutput()
+            repo_map = RepoMap(root=temp_dir, io=io)
             other_files = [
                 os.path.join(temp_dir, test_file1),
                 os.path.join(temp_dir, test_file2),
@@ -83,7 +86,7 @@ print(my_function(3, 4))
     def test_check_for_ctags_failure(self):
         with patch("subprocess.run") as mock_run:
             mock_run.side_effect = Exception("ctags not found")
-            repo_map = RepoMap()
+            repo_map = RepoMap(io=InputOutput())
             self.assertFalse(repo_map.has_ctags)
 
     def test_check_for_ctags_success(self):
@@ -100,7 +103,7 @@ print(my_function(3, 4))
                     b' status = main()$/", "kind": "variable"}'
                 ),
             ]
-            repo_map = RepoMap()
+            repo_map = RepoMap(io=InputOutput())
             self.assertTrue(repo_map.has_ctags)
 
     def test_get_repo_map_without_ctags(self):
@@ -120,7 +123,7 @@ print(my_function(3, 4))
                 with open(os.path.join(temp_dir, file), "w") as f:
                     f.write("")
 
-            repo_map = RepoMap(root=temp_dir)
+            repo_map = RepoMap(root=temp_dir, io=InputOutput())
             repo_map.has_ctags = False  # force it off
 
             other_files = [os.path.join(temp_dir, file) for file in test_files]