diff --git a/ftplugin/ale-info.vim b/ftplugin/ale-info.vim
index c2c794b2..a982a1b6 100644
--- a/ftplugin/ale-info.vim
+++ b/ftplugin/ale-info.vim
@@ -19,4 +19,4 @@ let b:undo_ftplugin = get(b:, 'undo_ftplugin', 'execute')
 let b:undo_ftplugin .= ' | setlocal synmaxcol<'
 let b:undo_ftplugin .= ' | execute "silent! unmap <buffer> q"'
 let b:undo_ftplugin .= ' | execute "silent! nunmap <buffer> <space>"'
-let b:undo_ftplugin .= ' | delfunction! ALEInfoOpenHelp'
+let b:undo_ftplugin .= ' | if exists(''*ALEInfoOpenHelp'') | delfunction ALEInfoOpenHelp | endif'