diff --git a/setup/pi/setup-teslausb b/setup/pi/setup-teslausb
index 5877020..4cdf3f2 100644
--- a/setup/pi/setup-teslausb
+++ b/setup/pi/setup-teslausb
@@ -13,10 +13,10 @@ then
 fi
 
 function setup_progress () {
-  SETUP_LOGFILE=/boot/teslausb-headless-setup.log
+  local setup_logfile=/boot/teslausb-headless-setup.log
   if [ $HEADLESS_SETUP = "true" ]
   then
-    echo "$( date ) : $1" >> "$SETUP_LOGFILE"
+    echo "$( date ) : $1" >> "$setup_logfile"
   fi
     echo $1
 }