diff --git a/dbus-sdr/sensorcommands.cpp b/dbus-sdr/sensorcommands.cpp
index f0f99a3..7cbd29f 100644
--- a/dbus-sdr/sensorcommands.cpp
+++ b/dbus-sdr/sensorcommands.cpp
@@ -643,6 +643,11 @@
     std::string connection;
     std::string path;
 
+    if (sensnum == reservedSensorNumber)
+    {
+        return ipmi::responseInvalidFieldRequest();
+    }
+
     auto status = getSensorConnection(ctx, sensnum, connection, path);
     if (status)
     {
@@ -868,7 +873,7 @@
     uint8_t upperNonCritical, uint8_t upperCritical,
     uint8_t upperNonRecoverable)
 {
-    if (reserved)
+    if (sensorNum == reservedSensorNumber || reserved)
     {
         return ipmi::responseInvalidFieldRequest();
     }
@@ -1090,6 +1095,11 @@
     std::string connection;
     std::string path;
 
+    if (sensorNumber == reservedSensorNumber)
+    {
+        return ipmi::responseInvalidFieldRequest();
+    }
+
     auto status = getSensorConnection(ctx, sensorNumber, connection, path);
     if (status)
     {
@@ -1178,6 +1188,11 @@
     uint8_t deassertionEnabledLsb = 0;
     uint8_t deassertionEnabledMsb = 0;
 
+    if (sensorNum == reservedSensorNumber)
+    {
+        return ipmi::responseInvalidFieldRequest();
+    }
+
     auto status = getSensorConnection(ctx, sensorNum, connection, path);
     if (status)
     {