diff --git a/joint_trajectory_controller/src/joint_trajectory_controller.cpp b/joint_trajectory_controller/src/joint_trajectory_controller.cpp
index 2d03dbee69..4c4d0dfdb0 100644
--- a/joint_trajectory_controller/src/joint_trajectory_controller.cpp
+++ b/joint_trajectory_controller/src/joint_trajectory_controller.cpp
@@ -220,7 +220,7 @@ controller_interface::return_type JointTrajectoryController::update(
       }
       if (traj_contr_)
       {
-        // set start time of trajectory to traj_contr_
+        // switch RT buffer of traj_contr_
         traj_contr_->start();
       }
     }
@@ -1038,6 +1038,14 @@ controller_interface::CallbackReturn JointTrajectoryController::on_activate(
   {
     cmd_timeout_ = 0.0;
   }
+
+  // activate traj_contr_, e.g., update gains
+  if (traj_contr_ && traj_contr_->activate() == false)
+  {
+    RCLCPP_ERROR(get_node()->get_logger(), "Error during trajectory controller activation.");
+    return CallbackReturn::ERROR;
+  }
+
   return CallbackReturn::SUCCESS;
 }