diff --git a/phosphor-regulators/src/device.cpp b/phosphor-regulators/src/device.cpp
index bde41cc..7d80851 100644
--- a/phosphor-regulators/src/device.cpp
+++ b/phosphor-regulators/src/device.cpp
@@ -50,6 +50,12 @@
 
 void Device::clearErrorHistory()
 {
+    // Clear error history in phase fault detection, if defined
+    if (phaseFaultDetection)
+    {
+        phaseFaultDetection->clearErrorHistory();
+    }
+
     // Clear error history in each rail
     for (std::unique_ptr<Rail>& rail : rails)
     {
diff --git a/phosphor-regulators/test/device_tests.cpp b/phosphor-regulators/test/device_tests.cpp
index 5a7e853..5d9a0e4 100644
--- a/phosphor-regulators/test/device_tests.cpp
+++ b/phosphor-regulators/test/device_tests.cpp
@@ -243,24 +243,36 @@
 TEST_F(DeviceTests, ClearErrorHistory)
 {
     // Create SensorMonitoring.  Will fail with a DBus exception.
-    auto action = std::make_unique<MockAction>();
-    EXPECT_CALL(*action, execute)
-        .WillRepeatedly(Throw(TestSDBusError{"Unable to set sensor value"}));
-    std::vector<std::unique_ptr<Action>> actions{};
-    actions.emplace_back(std::move(action));
-    auto sensorMonitoring =
-        std::make_unique<SensorMonitoring>(std::move(actions));
+    std::unique_ptr<SensorMonitoring> sensorMonitoring{};
+    {
+        auto action = std::make_unique<MockAction>();
+        EXPECT_CALL(*action, execute)
+            .WillRepeatedly(Throw(TestSDBusError{"DBus Error"}));
+        std::vector<std::unique_ptr<Action>> actions{};
+        actions.emplace_back(std::move(action));
+        sensorMonitoring =
+            std::make_unique<SensorMonitoring>(std::move(actions));
+    }
 
     // Create Rail
     std::unique_ptr<Configuration> configuration{};
-    auto rail = std::make_unique<Rail>("vddr1", std::move(configuration),
+    auto rail = std::make_unique<Rail>("vdd", std::move(configuration),
                                        std::move(sensorMonitoring));
 
-    // Create Device that contains Rail
+    // Create PhaseFaultDetection.  Will log an N phase fault.
+    std::unique_ptr<PhaseFaultDetection> phaseFaultDetection{};
+    {
+        auto action = std::make_unique<LogPhaseFaultAction>(PhaseFaultType::n);
+        std::vector<std::unique_ptr<Action>> actions{};
+        actions.emplace_back(std::move(action));
+        phaseFaultDetection =
+            std::make_unique<PhaseFaultDetection>(std::move(actions));
+    }
+
+    // Create Device
     auto i2cInterface = std::make_unique<i2c::MockedI2CInterface>();
     std::unique_ptr<PresenceDetection> presenceDetection{};
     std::unique_ptr<Configuration> deviceConfiguration{};
-    std::unique_ptr<PhaseFaultDetection> phaseFaultDetection{};
     std::vector<std::unique_ptr<Rail>> rails{};
     rails.emplace_back(std::move(rail));
     Device device{"reg2",
@@ -272,40 +284,69 @@
                   std::move(phaseFaultDetection),
                   std::move(rails)};
 
-    // Create mock services
-    MockServices services{};
+    // Create lambda that sets MockServices expectations.  The lambda allows us
+    // to set the same expectations twice without duplicate code.
+    auto setExpectations = [](MockServices& services) {
+        // Set Journal service expectations:
+        // - 3 error messages for D-Bus errors
+        // - 3 error messages for inability to monitor sensors
+        // - 2 error messages for the N phase fault
+        MockJournal& journal = services.getMockJournal();
+        EXPECT_CALL(journal, logError(std::vector<std::string>{"DBus Error"}))
+            .Times(3);
+        EXPECT_CALL(journal, logError("Unable to monitor sensors for rail vdd"))
+            .Times(3);
+        EXPECT_CALL(
+            journal,
+            logError("n phase fault detected in regulator reg2: count=1"))
+            .Times(1);
+        EXPECT_CALL(
+            journal,
+            logError("n phase fault detected in regulator reg2: count=2"))
+            .Times(1);
 
-    // Expect Sensors service to be called 5+5=10 times
-    MockSensors& sensors = services.getMockSensors();
-    EXPECT_CALL(sensors, startRail).Times(10);
-    EXPECT_CALL(sensors, setValue).Times(0);
-    EXPECT_CALL(sensors, endRail).Times(10);
+        // Set ErrorLogging service expectations:
+        // - D-Bus error should be logged once for the D-Bus exceptions
+        // - N phase fault error should be logged once
+        MockErrorLogging& errorLogging = services.getMockErrorLogging();
+        EXPECT_CALL(errorLogging, logDBusError).Times(1);
+        EXPECT_CALL(errorLogging, logPhaseFault).Times(1);
 
-    // Expect Journal service to be called 3+3=6 times to log error messages
-    MockJournal& journal = services.getMockJournal();
-    EXPECT_CALL(journal, logError(A<const std::vector<std::string>&>()))
-        .Times(6);
-    EXPECT_CALL(journal, logError(A<const std::string&>())).Times(6);
+        // Set Sensors service expections:
+        // - startRail() and endRail() called 5 times
+        MockSensors& sensors = services.getMockSensors();
+        EXPECT_CALL(sensors, startRail).Times(5);
+        EXPECT_CALL(sensors, endRail).Times(5);
+    };
 
-    // Expect ErrorLogging service to be called 1+1=2 times to log a DBus error
-    MockErrorLogging& errorLogging = services.getMockErrorLogging();
-    EXPECT_CALL(errorLogging, logDBusError).Times(2);
-
-    // Monitor sensors 5 times.  Should fail every time, write to journal 3
-    // times, and log one error.
-    for (int i = 1; i <= 5; ++i)
+    // Monitor sensors and detect phase faults 5 times.  Verify errors logged.
     {
-        device.monitorSensors(services, *system, *chassis);
+        // Create mock services.  Set expectations via lambda.
+        MockServices services{};
+        setExpectations(services);
+
+        for (int i = 1; i <= 5; ++i)
+        {
+            device.monitorSensors(services, *system, *chassis);
+            device.detectPhaseFaults(services, *system, *chassis);
+        }
     }
 
     // Clear error history
     device.clearErrorHistory();
 
-    // Monitor sensors 5 times again.  Should fail every time, write to journal
-    // 3 times, and log one error.
-    for (int i = 1; i <= 5; ++i)
+    // Monitor sensors and detect phase faults 5 more times.  Verify errors
+    // logged again.
     {
-        device.monitorSensors(services, *system, *chassis);
+        // Create mock services.  Set expectations via lambda.
+        MockServices services{};
+        setExpectations(services);
+
+        for (int i = 1; i <= 5; ++i)
+        {
+            device.monitorSensors(services, *system, *chassis);
+            device.detectPhaseFaults(services, *system, *chassis);
+        }
     }
 }