diff --git a/selfdrive/selfdrived/selfdrived.py b/selfdrive/selfdrived/selfdrived.py
index 39f655d..5c13610 100755
--- a/selfdrive/selfdrived/selfdrived.py
+++ b/selfdrive/selfdrived/selfdrived.py
@@ -745,7 +745,16 @@ class SelfdriveD(GapButtonActions):
       self.is_ldw_enabled = self.params.get_bool("IsLdwEnabled")
       self.disengage_on_accelerator = self.params.get_bool("DisengageOnAccelerator")
       self.experimental_mode = self.params.get_bool("ExperimentalMode") and self.CP.openpilotLongitudinalControl
-      self.personality = self.params.get("LongitudinalPersonality", return_default=True)
+      # Params can be changed while selfdrived is running. Keep the live value in
+      # the same valid enum range enforced during startup; otherwise a stale value
+      # (for example 3) makes the alert callback lookup raise KeyError and kills
+      # selfdrived.
+      self.personality = get_sanitize_int_param(
+        "LongitudinalPersonality",
+        min(log.LongitudinalPersonality.schema.enumerants.values()),
+        max(log.LongitudinalPersonality.schema.enumerants.values()),
+        self.params,
+      )
       self.nav_exit_lane_change = self._read_nav_exit_lane_change()
       self.model_download_pending = self.params.get("ModelManager_DownloadIndex") is not None
 
diff --git a/selfdrive/selfdrived/tests/test_longitudinal_pref_persistence.py b/selfdrive/selfdrived/tests/test_longitudinal_pref_persistence.py
index b8e1c58..ba128f7 100644
--- a/selfdrive/selfdrived/tests/test_longitudinal_pref_persistence.py
+++ b/selfdrive/selfdrived/tests/test_longitudinal_pref_persistence.py
@@ -1,6 +1,6 @@
 from cereal import car
 
-from openpilot.selfdrive.selfdrived.selfdrived import _cleanup_startup_params
+from openpilot.selfdrive.selfdrived.selfdrived import _cleanup_startup_params, get_sanitize_int_param
 
 
 class DummyParams:
@@ -21,3 +21,20 @@ class TestLongitudinalPrefPersistence:
     _cleanup_startup_params(cp, params)
 
     assert params.removed == []
+
+  def test_invalid_personality_is_clamped_before_use(self):
+    class ParamsWithInvalidPersonality:
+      def __init__(self):
+        self.value = 3
+
+      def get(self, key: str, return_default: bool = False) -> int:
+        assert key == "LongitudinalPersonality"
+        return self.value
+
+      def put(self, key: str, value: int) -> None:
+        assert key == "LongitudinalPersonality"
+        self.value = value
+
+    params = ParamsWithInvalidPersonality()
+    assert get_sanitize_int_param("LongitudinalPersonality", 0, 2, params) == 2
+    assert params.value == 2