diff --git a/fhem/FHEM/00_Neuron.pm b/fhem/FHEM/00_Neuron.pm
index 28473fed1..e72e7c5dc 100644
--- a/fhem/FHEM/00_Neuron.pm
+++ b/fhem/FHEM/00_Neuron.pm
@@ -35,6 +35,7 @@ use strict;
 use warnings;
 
 require "HttpUtils.pm";
+require "DevIo.pm";
 
 my @clients = qw(
 NeuronPin