diff --git a/service/src/com/android/server/connectivity/CarrierPrivilegeAuthenticator.java b/service/src/com/android/server/connectivity/CarrierPrivilegeAuthenticator.java
index 4325763c5e..88aa329885 100644
--- a/service/src/com/android/server/connectivity/CarrierPrivilegeAuthenticator.java
+++ b/service/src/com/android/server/connectivity/CarrierPrivilegeAuthenticator.java
@@ -35,6 +35,7 @@ import android.os.Process;
 import android.telephony.SubscriptionManager;
 import android.telephony.TelephonyManager;
 import android.util.Log;
+import android.util.SparseIntArray;
 
 import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
@@ -63,7 +64,7 @@ public class CarrierPrivilegeAuthenticator extends BroadcastReceiver {
     private final TelephonyManagerShim mTelephonyManagerShim;
     private final TelephonyManager mTelephonyManager;
     @GuardedBy("mLock")
-    private int[] mCarrierServiceUid;
+    private final SparseIntArray mCarrierServiceUid = new SparseIntArray(2 /* initialCapacity */);
     @GuardedBy("mLock")
     private int mModemCount = 0;
     private final Object mLock = new Object();
@@ -75,7 +76,7 @@ public class CarrierPrivilegeAuthenticator extends BroadcastReceiver {
 
     public CarrierPrivilegeAuthenticator(@NonNull final Context c,
             @NonNull final TelephonyManager t,
-            @NonNull final TelephonyManagerShimImpl telephonyManagerShim) {
+            @NonNull final TelephonyManagerShim telephonyManagerShim) {
         mContext = c;
         mTelephonyManager = t;
         mTelephonyManagerShim = telephonyManagerShim;
@@ -91,17 +92,7 @@ public class CarrierPrivilegeAuthenticator extends BroadcastReceiver {
 
     public CarrierPrivilegeAuthenticator(@NonNull final Context c,
             @NonNull final TelephonyManager t) {
-        mContext = c;
-        mTelephonyManager = t;
-        mTelephonyManagerShim = TelephonyManagerShimImpl.newInstance(mTelephonyManager);
-        mThread = new HandlerThread(TAG);
-        mThread.start();
-        mHandler = new Handler(mThread.getLooper()) {};
-        synchronized (mLock) {
-            mModemCount = mTelephonyManager.getActiveModemCount();
-            registerForCarrierChanges();
-            updateCarrierServiceUid();
-        }
+        this(c, t, TelephonyManagerShimImpl.newInstance(t));
     }
 
     /**
@@ -233,9 +224,9 @@ public class CarrierPrivilegeAuthenticator extends BroadcastReceiver {
     @VisibleForTesting
     void updateCarrierServiceUid() {
         synchronized (mLock) {
-            mCarrierServiceUid = new int[mModemCount];
+            mCarrierServiceUid.clear();
             for (int i = 0; i < mModemCount; i++) {
-                mCarrierServiceUid[i] = getCarrierServicePackageUidForSlot(i);
+                mCarrierServiceUid.put(i, getCarrierServicePackageUidForSlot(i));
             }
         }
     }
@@ -244,11 +235,8 @@ public class CarrierPrivilegeAuthenticator extends BroadcastReceiver {
     int getCarrierServiceUidForSubId(int subId) {
         final int slotId = getSlotIndex(subId);
         synchronized (mLock) {
-            if (slotId != SubscriptionManager.INVALID_SIM_SLOT_INDEX && slotId < mModemCount) {
-                return mCarrierServiceUid[slotId];
-            }
+            return mCarrierServiceUid.get(slotId, Process.INVALID_UID);
         }
-        return Process.INVALID_UID;
     }
 
     @VisibleForTesting