diff --git a/control/mpc_lateral_controller/include/mpc_lateral_controller/mpc_lateral_controller.hpp b/control/mpc_lateral_controller/include/mpc_lateral_controller/mpc_lateral_controller.hpp
index dce631ce98224..f795a60dcefbb 100644
--- a/control/mpc_lateral_controller/include/mpc_lateral_controller/mpc_lateral_controller.hpp
+++ b/control/mpc_lateral_controller/include/mpc_lateral_controller/mpc_lateral_controller.hpp
@@ -97,7 +97,7 @@ class MpcLateralController : public trajectory_follower::LateralControllerBase
   // trajectory buffer for detecting new trajectory
   std::deque<Trajectory> m_trajectory_buffer;
 
-  void setStatus(diagnostic_updater::DiagnosticStatusWrapper & stat, const bool & m_is_mpc_solved);
+  void setStatus(diagnostic_updater::DiagnosticStatusWrapper & stat);
 
   void setupDiag();
 
diff --git a/control/mpc_lateral_controller/src/mpc_lateral_controller.cpp b/control/mpc_lateral_controller/src/mpc_lateral_controller.cpp
index 65166553cfbeb..12a0d9c8620bb 100644
--- a/control/mpc_lateral_controller/src/mpc_lateral_controller.cpp
+++ b/control/mpc_lateral_controller/src/mpc_lateral_controller.cpp
@@ -232,7 +232,7 @@ std::shared_ptr<SteeringOffsetEstimator> MpcLateralController::createSteerOffset
 }
 
 void MpcLateralController::setStatus(
-  diagnostic_updater::DiagnosticStatusWrapper & stat, const bool & m_is_mpc_solved)
+  diagnostic_updater::DiagnosticStatusWrapper & stat)
 {
   if (m_is_mpc_solved) {
     stat.summary(diagnostic_msgs::msg::DiagnosticStatus::OK, "MPC succeeded.");
@@ -249,7 +249,7 @@ void MpcLateralController::setupDiag()
 
   d->add("MPC_solve_checker", [&](auto & stat) {
     setStatus(
-      stat, m_is_mpc_solved);
+      stat);
   });
 }