diff --git a/telephony/java/android/telephony/CarrierConfigManager.java b/telephony/java/android/telephony/CarrierConfigManager.java
index de35c00c8059c..0ebd30145d7e1 100644
--- a/telephony/java/android/telephony/CarrierConfigManager.java
+++ b/telephony/java/android/telephony/CarrierConfigManager.java
@@ -3723,7 +3723,7 @@ public class CarrierConfigManager {
         sDefaults.putInt(KEY_IMS_DTMF_TONE_DELAY_INT, 0);
         sDefaults.putInt(KEY_CDMA_DTMF_TONE_DELAY_INT, 100);
         sDefaults.putBoolean(KEY_CALL_FORWARDING_MAP_NON_NUMBER_TO_VOICEMAIL_BOOL, false);
-        sDefaults.putBoolean(KEY_IGNORE_RTT_MODE_SETTING_BOOL, false);
+        sDefaults.putBoolean(KEY_IGNORE_RTT_MODE_SETTING_BOOL, true);
         sDefaults.putInt(KEY_CDMA_3WAYCALL_FLASH_DELAY_INT , 0);
         sDefaults.putBoolean(KEY_SUPPORT_ADHOC_CONFERENCE_CALLS_BOOL, false);
         sDefaults.putBoolean(KEY_SUPPORT_ADD_CONFERENCE_PARTICIPANTS_BOOL, false);