Index: firmware/App/Drivers/SafetyShutdown.c
===================================================================
diff -u -r9e5ee62245eb2a73b167eabd6c274a71a76a7b0e -re5e7a37f5f1e2942630f748be23eac9f452af3aa
--- firmware/App/Drivers/SafetyShutdown.c	(.../SafetyShutdown.c)	(revision 9e5ee62245eb2a73b167eabd6c274a71a76a7b0e)
+++ firmware/App/Drivers/SafetyShutdown.c	(.../SafetyShutdown.c)	(revision e5e7a37f5f1e2942630f748be23eac9f452af3aa)
@@ -36,8 +36,9 @@
 #define SAFETY_SHUTDOWN_POST_TIMEOUT_MS     500                                     ///< Safety shutdown POST test timeout (in ms).
 #define SAFETY_SHUTDOWN_RECOVERY_TIME_MS    500                                     ///< After safety shutdown POST test, wait this long (in ms) to recover before moving on.
 
-#define MAX_24V_LEVEL_ON_SAFETY_SHUTDOWN    5.0F                                    ///< Maximum voltage on 24V line when safety shutdown asserted.
-#define MIN_24V_LEVEL_ON_SAFETY_RECOVER     22.6F                                   ///< Minimum voltage on 24V line when safety shutdown is recovered.
+#define MAX_24V_LEVEL_ON_SAFETY_SHUTDOWN     5.0F                                   ///< Maximum voltage on 24V line when safety shutdown asserted.
+#define MAX_ISOLATED_24V_LEVEL_ON_SS_EXPIRED 22.6F                                  ///< Maximum voltage on isolated 24V line when watchdog is expired. 10% of 24V.
+#define MIN_24V_LEVEL_ON_SAFETY_RECOVER      22.6F                                  ///< Minimum voltage on 24V line when safety shutdown is recovered.
 
 /// Enumeration of safety shutdown self-test states.
 typedef enum Safety_Shutdown_Self_Test_States
@@ -126,7 +127,8 @@
         case SAFETY_SHUTDOWN_SELF_TEST_STATE_IN_PROGRESS:
             if ( TRUE == didTimeout( safetyShutdownSelfTestTimerCount, SAFETY_SHUTDOWN_POST_TIMEOUT_MS ) )
             {
-                F32 v24 = getIntADCVoltageConverted( INT_ADC_SECONDARY_HEATER_24_VOLTS );
+                F32 v24         = getIntADCVoltageConverted( INT_ADC_SECONDARY_HEATER_24_VOLTS );
+                F32 isolatedV24 = getMonitoredLineLevel( MONITORED_LINE_24V_POWER_PRIM_HTR_V );
 
                 // Verify 24V is down when w.d. expired
                 if ( v24 > MAX_24V_LEVEL_ON_SAFETY_SHUTDOWN )
@@ -144,11 +146,13 @@
         case SAFETY_SHUTDOWN_SELF_TEST_STATE_RECOVER:
             if ( TRUE == didTimeout( safetyShutdownSelfTestTimerCount, SAFETY_SHUTDOWN_RECOVERY_TIME_MS ) )
             {
-                F32 v24 = getIntADCVoltageConverted( INT_ADC_SECONDARY_HEATER_24_VOLTS );
+                F32 v24         = getIntADCVoltageConverted( INT_ADC_SECONDARY_HEATER_24_VOLTS );
+                F32 isolatedV24 = getMonitoredLineLevel( MONITORED_LINE_24V_POWER_PRIM_HTR_V );
 
                 // Verify 24V is down when w.d. recovered
-                if ( v24 < MIN_24V_LEVEL_ON_SAFETY_RECOVER )   // TODO - If issue persisted talk with systems why 24V does not recover fully.
+                if ( v24 < MIN_24V_LEVEL_ON_SAFETY_RECOVER )
                 {
+                    // TODO - If issue persisted talk with systems why 24V does not recover fully.
                     SET_ALARM_WITH_2_F32_DATA( ALARM_ID_DG_SAFETY_SHUTDOWN_POST_TEST_FAILED, 2.0, v24 );
                     safetyShutdownSelfTestStatus = SELF_TEST_STATUS_FAILED;
                 }