diff --git a/docs/target-architecture.md b/docs/target-architecture.md
index 7f455b8f..de7987db 100644
--- a/docs/target-architecture.md
+++ b/docs/target-architecture.md
@@ -43,7 +43,8 @@ is explicitly deployed.
 - Redis is not the long-term historical store.
 - `event-file-store` Parquet/DuckDB is not the default history store.
 - `telemetry_fields` parsing is not handled by this project when a separate
-  field parsing service owns that job.
+  field parsing service owns that job; the `telemetry_fields` query API is
+  also disabled by default unless `TDENGINE_TELEMETRY_FIELDS_ENABLED=true`.
 
 ## Runtime Responsibilities
 
diff --git a/modules/apps/vehicle-history-app/src/test/java/com/lingniu/ingest/historyapp/VehicleHistoryAppCompositionTest.java b/modules/apps/vehicle-history-app/src/test/java/com/lingniu/ingest/historyapp/VehicleHistoryAppCompositionTest.java
index 2324b2c6..6fed29bc 100644
--- a/modules/apps/vehicle-history-app/src/test/java/com/lingniu/ingest/historyapp/VehicleHistoryAppCompositionTest.java
+++ b/modules/apps/vehicle-history-app/src/test/java/com/lingniu/ingest/historyapp/VehicleHistoryAppCompositionTest.java
@@ -121,7 +121,7 @@ class VehicleHistoryAppCompositionTest {
                     assertThat(context).hasSingleBean(Gb32960DecodedFrameService.class);
                     assertThat(context).hasSingleBean(LocationHistoryController.class);
                     assertThat(context).hasSingleBean(RawFrameHistoryController.class);
-                    assertThat(context).hasSingleBean(TelemetryFieldHistoryController.class);
+                    assertThat(context).doesNotHaveBean(TelemetryFieldHistoryController.class);
                     assertThat(context).doesNotHaveBean(Gb32960FrameController.class);
                     assertThat(context).doesNotHaveBean(Jt808LocationHistoryController.class);
                     assertThat(context).doesNotHaveBean(Gb32960NettyServer.class);
diff --git a/modules/services/event-history-service/src/main/java/com/lingniu/ingest/eventhistory/config/EventHistoryAutoConfiguration.java b/modules/services/event-history-service/src/main/java/com/lingniu/ingest/eventhistory/config/EventHistoryAutoConfiguration.java
index 882d6607..e1f444ef 100644
--- a/modules/services/event-history-service/src/main/java/com/lingniu/ingest/eventhistory/config/EventHistoryAutoConfiguration.java
+++ b/modules/services/event-history-service/src/main/java/com/lingniu/ingest/eventhistory/config/EventHistoryAutoConfiguration.java
@@ -154,6 +154,7 @@ public class EventHistoryAutoConfiguration {
 
     @Bean
     @ConditionalOnBean(TdengineHistoryReader.class)
+    @ConditionalOnProperty(prefix = "lingniu.ingest.tdengine-history", name = "telemetry-fields-enabled", havingValue = "true")
     @ConditionalOnMissingBean
     public TelemetryFieldHistoryController telemetryFieldHistoryController(TdengineHistoryReader reader) {
         return new TelemetryFieldHistoryController(reader);
diff --git a/modules/services/event-history-service/src/test/java/com/lingniu/ingest/eventhistory/config/EventHistoryAutoConfigurationTest.java b/modules/services/event-history-service/src/test/java/com/lingniu/ingest/eventhistory/config/EventHistoryAutoConfigurationTest.java
index e213c791..c855b934 100644
--- a/modules/services/event-history-service/src/test/java/com/lingniu/ingest/eventhistory/config/EventHistoryAutoConfigurationTest.java
+++ b/modules/services/event-history-service/src/test/java/com/lingniu/ingest/eventhistory/config/EventHistoryAutoConfigurationTest.java
@@ -120,14 +120,14 @@ class EventHistoryAutoConfigurationTest {
     }
 
     @Test
-    void createsGenericLocationAndTelemetryControllersWhenTdengineReaderExists() {
+    void createsGenericLocationAndRawControllersWithoutTelemetryFieldsByDefault() {
         contextRunner
                 .withPropertyValues("lingniu.ingest.event-history.enabled=true")
                 .withBean(TdengineHistoryReader.class, () -> mock(TdengineHistoryReader.class))
                 .run(context -> {
                     assertThat(context).hasSingleBean(LocationHistoryController.class);
                     assertThat(context).hasSingleBean(RawFrameHistoryController.class);
-                    assertThat(context).hasSingleBean(TelemetryFieldHistoryController.class);
+                    assertThat(context).doesNotHaveBean(TelemetryFieldHistoryController.class);
                     assertThat(context).doesNotHaveBean(Jt808LocationHistoryController.class);
                     assertThat(context).doesNotHaveBean(Jt808RawFrameHistoryController.class);
                 });
@@ -152,9 +152,11 @@ class EventHistoryAutoConfigurationTest {
     }
 
     @Test
-    void createsTelemetryFieldHistoryControllerWhenTdengineReaderExists() {
+    void createsTelemetryFieldHistoryControllerWhenTelemetryFieldsAreEnabled() {
         contextRunner
-                .withPropertyValues("lingniu.ingest.event-history.enabled=true")
+                .withPropertyValues(
+                        "lingniu.ingest.event-history.enabled=true",
+                        "lingniu.ingest.tdengine-history.telemetry-fields-enabled=true")
                 .withBean(TdengineHistoryReader.class, () -> mock(TdengineHistoryReader.class))
                 .run(context -> assertThat(context).hasSingleBean(TelemetryFieldHistoryController.class));
     }