diff --git a/apps/frontend/src/app/app.routes.ts b/apps/frontend/src/app/app.routes.ts
index de0315f..40e814f 100644
--- a/apps/frontend/src/app/app.routes.ts
+++ b/apps/frontend/src/app/app.routes.ts
@@ -24,10 +24,10 @@ export const routes: Routes = [
       import('./features/sites/site-detail/site-detail').then((m) => m.SiteDetail),
   },
   {
-  path: 'monitoring/sensors',
-  canActivate: [authGuard],
-  data: { role: 'admin' },
-  loadComponent: () =>
-    import('./features/monitoring/sensor-status/sensor-status').then((m) => m.SensorStatusView),
-},
+    path: 'monitoring/sensors',
+    canActivate: [authGuard],
+    data: { role: 'admin' },
+    loadComponent: () =>
+      import('./features/monitoring/sensor-status/sensor-status').then((m) => m.SensorStatusView),
+  },
 ];
diff --git a/apps/frontend/src/app/features/dashboard/dashboard.html b/apps/frontend/src/app/features/dashboard/dashboard.html
index 2f48539..f9a3fb2 100644
--- a/apps/frontend/src/app/features/dashboard/dashboard.html
+++ b/apps/frontend/src/app/features/dashboard/dashboard.html
@@ -12,7 +12,7 @@
     <div class="dashboard__actions">
       @if (auth.principal()?.role === 'admin') {
         <a routerLink="/monitoring/sensors" class="ev-link">Supervision des capteurs</a>
-       }
+      }
       <a routerLink="/sites" class="ev-link">Voir les sites</a>
       <ev-button
         class="logout-button"
diff --git a/apps/frontend/src/app/features/monitoring/sensor-status/sensor-status.html b/apps/frontend/src/app/features/monitoring/sensor-status/sensor-status.html
index e918c90..3497dd5 100644
--- a/apps/frontend/src/app/features/monitoring/sensor-status/sensor-status.html
+++ b/apps/frontend/src/app/features/monitoring/sensor-status/sensor-status.html
@@ -28,15 +28,17 @@
 
           <ul class="sensor-list">
             @for (entry of sensorEntries; track entry[0]) {
+              @let diagnostic = sensorOf(site.sensors, entry[0]);
               <li class="sensor-item">
-                <span
-                  class="sensor-dot"
-                  [class]="'sensor-dot--' + sensorOf(site.sensors, entry[0]).status"
-                ></span>
+                <span class="sensor-dot" [class]="'sensor-dot--' + diagnostic.status"></span>
                 <span class="sensor-item__label">{{ entry[1] }}</span>
-                @if (sensorOf(site.sensors, entry[0]).status === 'failing') {
+                @if (diagnostic.status === 'failing') {
                   <span class="sensor-item__since">
-                    depuis {{ sensorOf(site.sensors, entry[0]).since | date: 'short' }}
+                    @if (diagnostic.since; as since) {
+                      dernière lecture le {{ since | date: 'dd/MM/yyyy HH:mm' }}
+                    } @else {
+                      aucune lecture reçue
+                    }
                   </span>
                 }
               </li>
diff --git a/apps/frontend/src/app/features/monitoring/sensor-status/sensor-status.spec.ts b/apps/frontend/src/app/features/monitoring/sensor-status/sensor-status.spec.ts
index 189e241..2e6e84e 100644
--- a/apps/frontend/src/app/features/monitoring/sensor-status/sensor-status.spec.ts
+++ b/apps/frontend/src/app/features/monitoring/sensor-status/sensor-status.spec.ts
@@ -79,21 +79,44 @@ describe('SensorStatusView', () => {
     expect(component.sensorOf(OK_SENSORS, 'temperature')).toEqual({ status: 'ok', since: null });
   });
 
-  it('affiche la date depuis quand un capteur est en panne', () => {
-  const sensors: SiteSensors = {
-    ...OK_SENSORS,
-    temperature: { status: 'failing', since: '2026-09-18T08:00:00' },
-  };
-  sensorsMock.getStatus.mockReturnValue(
-    of({
-      timestamp: '2026-09-18T08:00:00',
-      sites: [{ site_id: 'SITE001', site_name: 'Bureau Test', overall: 'degraded', sensors }],
-    })
-  );
+  it('affiche la date de la dernière lecture reçue pour un capteur en panne', () => {
+    const sensors: SiteSensors = {
+      ...OK_SENSORS,
+      temperature: { status: 'failing', since: '2026-09-18T08:00:00' },
+    };
+    sensorsMock.getStatus.mockReturnValue(
+      of({
+        timestamp: '2026-09-18T08:00:00',
+        sites: [{ site_id: 'SITE001', site_name: 'Bureau Test', overall: 'degraded', sensors }],
+      })
+    );
 
-  const fixture = TestBed.createComponent(SensorStatusView);
-  fixture.detectChanges();
+    const fixture = TestBed.createComponent(SensorStatusView);
+    fixture.detectChanges();
 
-  expect(fixture.nativeElement.textContent).toContain('depuis');
+    expect(fixture.nativeElement.textContent).toContain('dernière lecture le');
+    expect(fixture.nativeElement.textContent).toContain('18/09/2026 08:00');
+  });
+
+  it("annonce l'absence de lecture quand un site n'en a jamais reçu", () => {
+    const sensors: SiteSensors = {
+      consumption: { status: 'failing', since: null },
+      electrical: { status: 'failing', since: null },
+      temperature: { status: 'failing', since: null },
+      humidity: { status: 'failing', since: null },
+      network: { status: 'failing', since: null },
+    };
+    sensorsMock.getStatus.mockReturnValue(
+      of({
+        timestamp: '2026-09-18T08:00:00',
+        sites: [{ site_id: 'SITE001', site_name: 'Bureau Test', overall: 'critical', sensors }],
+      })
+    );
+
+    const fixture = TestBed.createComponent(SensorStatusView);
+    fixture.detectChanges();
+
+    expect(fixture.nativeElement.textContent).toContain('aucune lecture reçue');
+    expect(fixture.nativeElement.textContent).not.toContain('dernière lecture le');
   });
 });