diff --git a/src/TachSensor.cpp b/src/TachSensor.cpp
index 46f5389..23ae477 100644
--- a/src/TachSensor.cpp
+++ b/src/TachSensor.cpp
@@ -197,7 +197,13 @@
 
 void TachSensor::checkThresholds(void)
 {
+    if (!isPowerOn())
+    {
+        return;
+    }
+
     bool status = thresholds::checkThresholds(this);
+
     if (redundancy && *redundancy)
     {
         (*redundancy)