diff --git a/src/com/android/settings/deviceinfo/simstatus/SimStatusDialogController.java b/src/com/android/settings/deviceinfo/simstatus/SimStatusDialogController.java
index 9858ad21026..e3f217dba3a 100644
--- a/src/com/android/settings/deviceinfo/simstatus/SimStatusDialogController.java
+++ b/src/com/android/settings/deviceinfo/simstatus/SimStatusDialogController.java
@@ -140,6 +140,7 @@ public class SimStatusDialogController implements LifecycleObserver, OnResume, O
 
     private SubscriptionInfo mSubscriptionInfo;
     private TelephonyDisplayInfo mTelephonyDisplayInfo;
+    private ServiceState mServiceState;
 
     private final int mSlotIndex;
     private TelephonyManager mTelephonyManager;
@@ -437,6 +438,9 @@ public class SimStatusDialogController implements LifecycleObserver, OnResume, O
         final int state = Utils.getCombinedServiceState(serviceState);
         if (!Utils.isInService(serviceState)) {
             resetSignalStrength();
+        } else if (mServiceState != null && !Utils.isInService(mServiceState)) {
+            // If ServiceState changed from out of service -> in service, update signal strength.
+            updateSignalStrength(mTelephonyManager.getSignalStrength());
         }
 
         String serviceStateValue;
@@ -484,7 +488,7 @@ public class SimStatusDialogController implements LifecycleObserver, OnResume, O
         }
 
         ServiceState serviceState = mTelephonyManager.getServiceState();
-        if (serviceState == null || !Utils.isInService(serviceState)) {
+        if (!Utils.isInService(serviceState)) {
             return;
         }
 
@@ -767,6 +771,7 @@ public class SimStatusDialogController implements LifecycleObserver, OnResume, O
                 updateNetworkProvider();
                 updateServiceState(serviceState);
                 updateRoamingStatus(serviceState);
+                mServiceState = serviceState;
             }
 
             @Override