diff --git a/vehicle-data-platform/apps/api/internal/platform/handler_test.go b/vehicle-data-platform/apps/api/internal/platform/handler_test.go
index b36c42ee..f05874ad 100644
--- a/vehicle-data-platform/apps/api/internal/platform/handler_test.go
+++ b/vehicle-data-platform/apps/api/internal/platform/handler_test.go
@@ -92,6 +92,18 @@ func TestHandlerVehicleCoverage(t *testing.T) {
 	if body.Data.Items[0].ServiceStatus.Status != "degraded" {
 		t.Fatalf("coverage row should expose degraded status, got %+v", body.Data.Items[0].ServiceStatus)
 	}
+	var rawBody struct {
+		Data Page[struct {
+			VIN              string   `json:"vin"`
+			MissingProtocols []string `json:"missingProtocols"`
+		}] `json:"data"`
+	}
+	if err := json.Unmarshal(rec.Body.Bytes(), &rawBody); err != nil {
+		t.Fatalf("response JSON should decode missing source evidence: %v body=%s", err, rec.Body.String())
+	}
+	if len(rawBody.Data.Items) == 0 || !containsString(rawBody.Data.Items[0].MissingProtocols, "YUTONG_MQTT") {
+		t.Fatalf("coverage row should expose missing canonical protocols, got %+v body=%s", rawBody.Data.Items, rec.Body.String())
+	}
 }
 
 func TestHandlerVehicleCoverageFiltersServiceStatus(t *testing.T) {
diff --git a/vehicle-data-platform/apps/api/internal/platform/mock_store.go b/vehicle-data-platform/apps/api/internal/platform/mock_store.go
index 901091f5..26374e4f 100644
--- a/vehicle-data-platform/apps/api/internal/platform/mock_store.go
+++ b/vehicle-data-platform/apps/api/internal/platform/mock_store.go
@@ -132,6 +132,7 @@ func (m *MockStore) VehicleCoverage(_ context.Context, query url.Values) (Page[V
 	}
 	items := make([]VehicleCoverageRow, 0, len(byVIN))
 	for _, row := range byVIN {
+		row.MissingProtocols = missingCanonicalProtocols(row.Protocols)
 		row.ServiceStatus = buildVehicleCoverageServiceStatus(*row)
 		if keepCoverageRow(*row, query) {
 			items = append(items, *row)
diff --git a/vehicle-data-platform/apps/api/internal/platform/model.go b/vehicle-data-platform/apps/api/internal/platform/model.go
index deecb28d..07831c67 100644
--- a/vehicle-data-platform/apps/api/internal/platform/model.go
+++ b/vehicle-data-platform/apps/api/internal/platform/model.go
@@ -55,6 +55,7 @@ type VehicleCoverageRow struct {
 	Phone             string                `json:"phone"`
 	OEM               string                `json:"oem"`
 	Protocols         []string              `json:"protocols"`
+	MissingProtocols  []string              `json:"missingProtocols"`
 	SourceCount       int                   `json:"sourceCount"`
 	OnlineSourceCount int                   `json:"onlineSourceCount"`
 	Online            bool                  `json:"online"`
diff --git a/vehicle-data-platform/apps/api/internal/platform/production_store.go b/vehicle-data-platform/apps/api/internal/platform/production_store.go
index 94f69ca5..7227bbce 100644
--- a/vehicle-data-platform/apps/api/internal/platform/production_store.go
+++ b/vehicle-data-platform/apps/api/internal/platform/production_store.go
@@ -268,6 +268,7 @@ func (s *ProductionStore) VehicleCoverage(ctx context.Context, query url.Values)
 			return Page[VehicleCoverageRow]{}, err
 		}
 		row.Protocols = splitCSV(protocols)
+		row.MissingProtocols = missingCanonicalProtocols(row.Protocols)
 		row.Online = online == 1
 		row.ServiceStatus = buildVehicleCoverageServiceStatus(row)
 		items = append(items, row)
diff --git a/vehicle-data-platform/apps/api/internal/platform/service.go b/vehicle-data-platform/apps/api/internal/platform/service.go
index fcc20d5b..81af4fbe 100644
--- a/vehicle-data-platform/apps/api/internal/platform/service.go
+++ b/vehicle-data-platform/apps/api/internal/platform/service.go
@@ -58,6 +58,16 @@ type Service struct {
 
 var canonicalVehicleProtocols = []string{"GB32960", "JT808", "YUTONG_MQTT"}
 
+func missingCanonicalProtocols(protocols []string) []string {
+	missing := make([]string, 0, len(canonicalVehicleProtocols))
+	for _, protocol := range canonicalVehicleProtocols {
+		if !containsString(protocols, protocol) {
+			missing = append(missing, protocol)
+		}
+	}
+	return missing
+}
+
 func NewService(store Store) *Service {
 	return &Service{store: store}
 }
diff --git a/vehicle-data-platform/apps/web/src/api/types.ts b/vehicle-data-platform/apps/web/src/api/types.ts
index 81aafd88..c838a78c 100644
--- a/vehicle-data-platform/apps/web/src/api/types.ts
+++ b/vehicle-data-platform/apps/web/src/api/types.ts
@@ -52,6 +52,7 @@ export interface VehicleCoverageRow {
   phone: string;
   oem: string;
   protocols: string[];
+  missingProtocols: string[];
   sourceCount: number;
   onlineSourceCount: number;
   online: boolean;
diff --git a/vehicle-data-platform/apps/web/src/pages/Vehicles.tsx b/vehicle-data-platform/apps/web/src/pages/Vehicles.tsx
index 50d92882..ca774597 100644
--- a/vehicle-data-platform/apps/web/src/pages/Vehicles.tsx
+++ b/vehicle-data-platform/apps/web/src/pages/Vehicles.tsx
@@ -125,6 +125,17 @@ export function Vehicles({
           </Space>
         )
       },
+      {
+        title: '缺失来源',
+        width: 220,
+        render: (_: unknown, row: VehicleCoverageRow) => (
+          <Space spacing={4} wrap>
+            {(row.missingProtocols ?? []).length > 0
+              ? row.missingProtocols.map((protocol) => <Tag key={protocol} color="orange">缺 {protocol}</Tag>)
+              : <Tag color="green">完整</Tag>}
+          </Space>
+        )
+      },
       { title: '证据覆盖', width: 120, render: (_: unknown, row: VehicleCoverageRow) => sourceEvidenceText(row) },
       { title: '在线', width: 90, render: (_: unknown, row: VehicleCoverageRow) => <StatusTag status={row.online ? 'ok' : 'offline'} /> },
       { title: '最后在线', dataIndex: 'lastSeen', width: 170 },
diff --git a/vehicle-data-platform/apps/web/src/test/App.test.tsx b/vehicle-data-platform/apps/web/src/test/App.test.tsx
index fae83056..d2216a99 100644
--- a/vehicle-data-platform/apps/web/src/test/App.test.tsx
+++ b/vehicle-data-platform/apps/web/src/test/App.test.tsx
@@ -445,6 +445,7 @@ test('filters vehicle list by missing source evidence', async () => {
               phone: '13307795425',
               oem: 'G7s',
               protocols: ['GB32960', 'JT808'],
+              missingProtocols: ['YUTONG_MQTT'],
               sourceCount: 2,
               onlineSourceCount: 0,
               online: false,
@@ -472,9 +473,13 @@ test('filters vehicle list by missing source evidence', async () => {
 
   render(<App />);
 
-  expect(await screen.findByText('缺失来源')).toBeInTheDocument();
+  await waitFor(() => {
+    expect(screen.getAllByText('缺失来源').length).toBeGreaterThanOrEqual(2);
+  });
+  expect(screen.getAllByText('缺 YUTONG_MQTT').length).toBeGreaterThanOrEqual(1);
   fireEvent.click(screen.getByTestId('missing-protocol-filter'));
-  fireEvent.click(await screen.findByText('缺 YUTONG_MQTT'));
+  const mqttOptions = await screen.findAllByText('缺 YUTONG_MQTT');
+  fireEvent.click(mqttOptions[mqttOptions.length - 1]);
   fireEvent.click(screen.getByRole('button', { name: '查询' }));
 
   await waitFor(() => {