diff --git a/DCCEXParser.cpp b/DCCEXParser.cpp
index 07c679b..bc79927 100644
--- a/DCCEXParser.cpp
+++ b/DCCEXParser.cpp
@@ -286,6 +286,8 @@ void DCCEXParser::parseOne(Print *stream, byte *com, RingStream * ringStream)
 
         if (direction < 0 || direction > 1)
             break; // invalid direction code
+	if (cab > 10239 || cab < 0)
+	    break; // beyond DCC range
 
         DCC::setThrottle(cab, tspeed, direction);
         if (params == 4) // send obsolete format T response
diff --git a/WiThrottle.cpp b/WiThrottle.cpp
index 69c5d87..aa92dc6 100644
--- a/WiThrottle.cpp
+++ b/WiThrottle.cpp
@@ -235,6 +235,10 @@ int WiThrottle::getLocoId(byte * cmd) {
 void WiThrottle::multithrottle(RingStream * stream, byte * cmd){ 
   char throttleChar=cmd[1];
   int locoid=getLocoId(cmd+3); // -1 for *
+  if (locoid > 10239 || locoid < -1) {
+    StringFormatter::send(stream, F("No valid DCC loco %d\n"), locoid);
+    return;
+  }
   byte * aval=cmd;
   while(*aval !=';' && *aval !='\0') aval++;
   if (*aval) aval+=2;  // skip ;>