diff --git a/src/ATBAPP/DeviceControllerDiag.cpp b/src/ATBAPP/DeviceControllerDiag.cpp
index e74775d..3d801db 100644
--- a/src/ATBAPP/DeviceControllerDiag.cpp
+++ b/src/ATBAPP/DeviceControllerDiag.cpp
@@ -57,6 +57,8 @@ void DeviceControllerDiag::private_startDiag()
     if (this->flagInterruptDiag) {
         qCritical() << "DeviceControllerDiag::private_startDiag() interrupted!";
         this->private_sendDiagEvent(DeviceController::State::E255);
+        this->isRequestRunning  = false;
+        this->flagInterruptDiag = false;
         return;
     }
 
@@ -89,6 +91,8 @@ void DeviceControllerDiag::sys_superviseSystem()
     if (this->flagInterruptDiag) {
         qCritical() << "DeviceControllerDiag::sys_superviseSystem() interrupted!";
         this->private_sendDiagEvent(DeviceController::State::E255);
+        this->flagInterruptDiag = false;
+        this->isRequestRunning  = false;
         return;
     }
 
@@ -97,6 +101,8 @@ void DeviceControllerDiag::sys_superviseSystem()
         // es gibt keinerlei gültige Daten vom DC
         qCritical() << "DeviceControllerDiag::sys_superviseSystem() no valid data!";
         this->private_sendDiagEvent(DeviceController::State::E254);
+        this->diagRequestTimeoutTimer->stop();
+        this->isRequestRunning  = false;
         return;
     }