diff --git a/lark/exceptions.py b/lark/exceptions.py
index 033275c..645b09c 100644
--- a/lark/exceptions.py
+++ b/lark/exceptions.py
@@ -72,11 +72,7 @@ class UnexpectedInput(LarkError):
 
 class UnexpectedCharacters(LexError, UnexpectedInput):
     def __init__(self, seq, lex_pos, line, column, allowed=None, considered_tokens=None, state=None, token_history=None):
-        
-        if isinstance(seq, bytes):
-            message = "No terminal defined for '%s' at line %d col %d" % (seq[lex_pos:lex_pos+1].decode("ascii", "backslashreplace"), line, column)
-        else:
-            message = "No terminal defined for '%s' at line %d col %d" % (seq[lex_pos], line, column)
+        message = "No terminal defined for '%s' at line %d col %d" % (seq[lex_pos], line, column)
 
         self.line = line
         self.column = column