diff --git a/custom_components/localthings/registry/capabilities/dishwasher.py b/custom_components/localthings/registry/capabilities/dishwasher.py
index 993bbe3..eed00d7 100644
--- a/custom_components/localthings/registry/capabilities/dishwasher.py
+++ b/custom_components/localthings/registry/capabilities/dishwasher.py
@@ -14,7 +14,6 @@ from .laundry import (
     bool_option_switch,
     cycle_select,
     drum_clean_cycles_remaining,
-    drum_clean_last_cleaned,
 )
 
 # ---------------------------------------------------------------------------
@@ -62,9 +61,14 @@ DISHWASHER_SETTINGS = Capability(
 # #258) DrumCleanProposal_/WashingTimes_/DrumCleanLog_ tokens riding on this
 # same options[] array -- a live dump confirmed the dishwasher reports the
 # identical trio (WashingTimes_18/DrumCleanProposal_20, plus a '|'-joined
-# DrumCleanLog_ history matching the dryer's multi-entry shape), so the
-# shared laundry.drum_clean_cycles_remaining/drum_clean_last_cleaned readers
-# apply unchanged; see laundry.py for the field semantics.
+# DrumCleanLog_ history matching the dryer's multi-entry shape), so
+# laundry.drum_clean_cycles_remaining applies unchanged.
+#
+# laundry.drum_clean_last_cleaned (DrumCleanLog_'s own newest entry) is
+# deliberately NOT wired up here (issue #398): a live dishwasher dump
+# showed it moving every 30-90s on its own, including well after a cycle
+# had already finished -- unlike the washer/dryer reports this reader was
+# built from (issues #9, #258), it never settles on a value worth showing.
 
 CYCLE_OPTIONS = Capability(
     href="/course/vs/0",
@@ -82,14 +86,6 @@ CYCLE_OPTIONS = Capability(
             exists_fn=lambda rep, resources: drum_clean_cycles_remaining(rep) is not None,
             rep_fn=drum_clean_cycles_remaining,
         ),
-        SensorDesc(
-            key="drum_clean_last_cleaned",
-            device_class="timestamp",
-            icon="mdi:calendar-clock",
-            entity_category="diagnostic",
-            exists_fn=lambda rep, resources: drum_clean_last_cleaned(rep) is not None,
-            rep_fn=drum_clean_last_cleaned,
-        ),
     ),
 )
 
diff --git a/tests/fixtures/golden/dishwasher.json b/tests/fixtures/golden/dishwasher.json
index c2df5f6..cf5b055 100644
--- a/tests/fixtures/golden/dishwasher.json
+++ b/tests/fixtures/golden/dishwasher.json
@@ -9,7 +9,6 @@
     "delay_start_hours",
     "diagnosis_status",
     "drum_clean_cycles_remaining",
-    "drum_clean_last_cleaned",
     "energy_kwh",
     "energy_saved_kwh",
     "finish_time",
@@ -43,7 +42,6 @@
     "samsung_dishwasher_diagnosis_start",
     "samsung_dishwasher_diagnosis_status",
     "samsung_dishwasher_drum_clean_cycles_remaining",
-    "samsung_dishwasher_drum_clean_last_cleaned",
     "samsung_dishwasher_energy_kwh",
     "samsung_dishwasher_energy_saved_kwh",
     "samsung_dishwasher_finish_time",
diff --git a/tests/test_dishwasher_capabilities.py b/tests/test_dishwasher_capabilities.py
index f49a139..05c3a5f 100644
--- a/tests/test_dishwasher_capabilities.py
+++ b/tests/test_dishwasher_capabilities.py
@@ -5,8 +5,6 @@ cycle_options, cycle_write) is tested in test_laundry_capabilities.py; here we
 check the dishwasher wiring and its device-specific options.
 """
 
-from datetime import UTC, datetime
-
 from custom_components.localthings.registry.capabilities import dishwasher
 from custom_components.localthings.registry.entities import SensorDesc, SwitchDesc
 
@@ -68,7 +66,13 @@ class TestDrumClean:
     """Drum Clean+ maintenance tracking shares washer.py's (issue #9) /
     dryer.py's (issue #258) options[]-array readers -- a live dishwasher
     dump confirmed the same WashingTimes_/DrumCleanProposal_/DrumCleanLog_
-    trio, so these entities are wired the same way here."""
+    trio, so drum_clean_cycles_remaining is wired the same way here.
+
+    drum_clean_last_cleaned is deliberately not (issue #398): a live dump
+    showed DrumCleanLog_'s newest entry moving every 30-90s on its own,
+    including well after a cycle had finished -- unlike the washer/dryer
+    reports this reader was built from (issues #9, #258), it never settles
+    on a value worth showing."""
 
     def test_cycles_remaining(self):
         desc = next(
@@ -87,28 +91,10 @@ class TestDrumClean:
         rep = {"x.com.samsung.da.options": ["WashingTimes_18", "DrumCleanProposal_20"]}
         assert desc.exists_fn(rep, {}) is True
 
-    def test_last_cleaned(self):
-        """A live dump's DrumCleanLog_ is a '|'-joined history (the dryer
-        shape, not the washer's single-entry one) -- the last entry wins."""
-        desc = next(
-            e for e in dishwasher.CYCLE_OPTIONS.entities if e.key == "drum_clean_last_cleaned"
+    def test_last_cleaned_is_not_wired(self):
+        assert not any(
+            e.key == "drum_clean_last_cleaned" for e in dishwasher.CYCLE_OPTIONS.entities
         )
-        assert desc.rep_fn is not None
-        rep = {
-            "x.com.samsung.da.options": [
-                "DrumCleanLog_2026-06-26T04:18:58|2026-06-28T00:36:34",
-            ]
-        }
-        assert desc.rep_fn(rep) == datetime(2026, 6, 28, 0, 36, 34, tzinfo=UTC)
-
-    def test_last_cleaned_missing(self):
-        desc = next(
-            e for e in dishwasher.CYCLE_OPTIONS.entities if e.key == "drum_clean_last_cleaned"
-        )
-        assert desc.rep_fn is not None
-        assert desc.rep_fn({"x.com.samsung.da.options": []}) is None
-        assert desc.exists_fn is not None
-        assert desc.exists_fn({"x.com.samsung.da.options": []}, {}) is False
 
 
 def test_diagnosis_status_is_a_translatable_enum():