diff --git a/apps/api/src/integrations/pl24/pl24.service.ts b/apps/api/src/integrations/pl24/pl24.service.ts
index 8fd940c..49172df 100644
--- a/apps/api/src/integrations/pl24/pl24.service.ts
+++ b/apps/api/src/integrations/pl24/pl24.service.ts
@@ -2058,6 +2058,37 @@ export class PL24Service {
         }
       }
 
+      // Fallback: the primary modelPath returned nothing (e.g. p5fiat is not mapped
+      // in BACKEND_MODEL_PATH yet). Try the other known P5 listing endpoints so an
+      // unmapped backend self-discovers its model list instead of silently seeding 0.
+      // Only runs when the primary yields nothing → no impact on mapped backends.
+      const candidatePaths = [
+        "/extern/vehicle/modelfamilies",
+        "/extern/vehicle/models",
+        "/extern/vehicle/modelFamilies",
+        "/extern/vehicle/catalogs",
+        "/extern/vehicle/scope",
+        "/extern/vehicles/vehiclesOverview",
+        "/extern/model/categories",
+      ].filter((p) => p !== modelPath);
+      for (const candidate of candidatePaths) {
+        try {
+          const cu = `${this.baseUrl}${catalogBase}${candidate}?lang=${this.language}&serviceName=${serviceName}`;
+          const cr = await fetch(cu, { method: "GET", headers, signal: AbortSignal.timeout(15000) });
+          if (!cr.ok) continue;
+          const cd = (await cr.json()) as Record<string, any>;
+          const cv = this.parseVehicleListResponse(cd, serviceName);
+          if (cv.length > 0) {
+            this.logger.log(
+              `fetchVehicleList: ${serviceName} discovered via ${candidate} (${cv.length} models) — pin BACKEND_MODEL_PATH["${backendKey}"]="${candidate}"`,
+            );
+            return cv;
+          }
+        } catch {
+          // try next candidate
+        }
+      }
+
       this.logger.log(`No vehicle list available for ${serviceName} (HTTP ${response.status})`);
       return [];
     } catch (err) {