diff --git a/packages/client/hmi-client/src/components/model/petrinet/tera-model-diagram.vue b/packages/client/hmi-client/src/components/model/petrinet/tera-model-diagram.vue
index ff398e4a36..203837ed4b 100644
--- a/packages/client/hmi-client/src/components/model/petrinet/tera-model-diagram.vue
+++ b/packages/client/hmi-client/src/components/model/petrinet/tera-model-diagram.vue
@@ -120,6 +120,9 @@ const resetZoom = async () => {
 };
 
 async function renderGraph() {
+	// Sanity guard
+	if (mmt.value.templates.length === 0) return;
+
 	renderer = getModelRenderer(
 		mmt.value,
 		graphElement.value as HTMLDivElement,