diff --git a/phosphor-power-supply/psu_manager.cpp b/phosphor-power-supply/psu_manager.cpp
new file mode 100644
index 0000000..54b20d8
--- /dev/null
+++ b/phosphor-power-supply/psu_manager.cpp
@@ -0,0 +1,40 @@
+#include "psu_manager.hpp"
+
+#include "utility.hpp"
+
+namespace phosphor
+{
+namespace power
+{
+namespace manager
+{
+
+void PSUManager::powerStateChanged(sdbusplus::message::message& msg)
+{
+    int32_t state = 0;
+    std::string msgSensor;
+    std::map<std::string, sdbusplus::message::variant<int32_t>> msgData;
+    msg.read(msgSensor, msgData);
+
+    // Check if it was the Present property that changed.
+    auto valPropMap = msgData.find("state");
+    if (valPropMap != msgData.end())
+    {
+        state = std::get<int32_t>(valPropMap->second);
+
+        // Power is on when state=1. Clear faults.
+        if (state)
+        {
+            powerOn = true;
+            clearFaults();
+        }
+        else
+        {
+            powerOn = false;
+        }
+    }
+}
+
+} // namespace manager
+} // namespace power
+} // namespace phosphor