diff --git a/map/map_loader/src/lanelet2_map_loader/lanelet2_map_loader_node.cpp b/map/map_loader/src/lanelet2_map_loader/lanelet2_map_loader_node.cpp
index ed527c38824fc..328808e04d9e0 100644
--- a/map/map_loader/src/lanelet2_map_loader/lanelet2_map_loader_node.cpp
+++ b/map/map_loader/src/lanelet2_map_loader/lanelet2_map_loader_node.cpp
@@ -92,13 +92,14 @@ lanelet::LaneletMapPtr Lanelet2MapLoaderNode::load_map(
   const double & map_origin_lat, const double & map_origin_lon)
 {
   lanelet::ErrorMessages errors{};
-  if (lanelet2_map_projector_type == "MGRS") {
+  if (lanelet2_map_projector_type == tier4_map_msgs::msg::MapProjectorInfo::MGRS) {
     lanelet::projection::MGRSProjector projector{};
     const lanelet::LaneletMapPtr map = lanelet::load(lanelet2_filename, projector, &errors);
     if (errors.empty()) {
       return map;
     }
-  } else if (lanelet2_map_projector_type == "LocalCartesianUTM") {
+  } else if (
+    lanelet2_map_projector_type == tier4_map_msgs::msg::MapProjectorInfo::LOCAL_CARTESIAN_UTM) {
     lanelet::GPSPoint position{map_origin_lat, map_origin_lon};
     lanelet::Origin origin{position};
     lanelet::projection::UtmProjector projector{origin};
@@ -106,7 +107,7 @@ lanelet::LaneletMapPtr Lanelet2MapLoaderNode::load_map(
     if (errors.empty()) {
       return map;
     }
-  } else if (lanelet2_map_projector_type == "local") {
+  } else if (lanelet2_map_projector_type == tier4_map_msgs::msg::MapProjectorInfo::LOCAL) {
     // Use MGRSProjector as parser
     lanelet::projection::MGRSProjector projector{};
     const lanelet::LaneletMapPtr map = lanelet::load(lanelet2_filename, projector, &errors);
diff --git a/map/map_projection_loader/src/load_info_from_lanelet2_map.cpp b/map/map_projection_loader/src/load_info_from_lanelet2_map.cpp
index f213432b66b50..18306e8d39e25 100644
--- a/map/map_projection_loader/src/load_info_from_lanelet2_map.cpp
+++ b/map/map_projection_loader/src/load_info_from_lanelet2_map.cpp
@@ -46,15 +46,15 @@ tier4_map_msgs::msg::MapProjectorInfo load_info_from_lanelet2_map(const std::str
 
   tier4_map_msgs::msg::MapProjectorInfo msg;
   if (is_local) {
-    msg.projector_type = "local";
+    msg.projector_type = tier4_map_msgs::msg::MapProjectorInfo::LOCAL;
   } else {
-    msg.projector_type = "MGRS";
+    msg.projector_type = tier4_map_msgs::msg::MapProjectorInfo::MGRS;
     msg.mgrs_grid = projector.getProjectedMGRSGrid();
   }
 
   // We assume that the vertical datum of the map is WGS84 when using lanelet2 map.
   // However, do note that this is not always true, and may cause problems in the future.
   // Thus, please consider using the map_projector_info.yaml instead of this deprecated function.
-  msg.vertical_datum = "WGS84";
+  msg.vertical_datum = tier4_map_msgs::msg::MapProjectorInfo::WGS84;
   return msg;
 }
diff --git a/map/map_projection_loader/src/map_projection_loader.cpp b/map/map_projection_loader/src/map_projection_loader.cpp
index ec38f0ff3642e..79083b755fb26 100644
--- a/map/map_projection_loader/src/map_projection_loader.cpp
+++ b/map/map_projection_loader/src/map_projection_loader.cpp
@@ -28,14 +28,14 @@ tier4_map_msgs::msg::MapProjectorInfo load_info_from_yaml(const std::string & fi
 
   tier4_map_msgs::msg::MapProjectorInfo msg;
   msg.projector_type = data["projector_type"].as<std::string>();
-  if (msg.projector_type == "MGRS") {
+  if (msg.projector_type == tier4_map_msgs::msg::MapProjectorInfo::MGRS) {
     msg.vertical_datum = data["vertical_datum"].as<std::string>();
     msg.mgrs_grid = data["mgrs_grid"].as<std::string>();
-  } else if (msg.projector_type == "LocalCartesianUTM") {
+  } else if (msg.projector_type == tier4_map_msgs::msg::MapProjectorInfo::LOCAL_CARTESIAN_UTM) {
     msg.vertical_datum = data["vertical_datum"].as<std::string>();
     msg.map_origin.latitude = data["map_origin"]["latitude"].as<double>();
     msg.map_origin.longitude = data["map_origin"]["longitude"].as<double>();
-  } else if (msg.projector_type == "local") {
+  } else if (msg.projector_type == tier4_map_msgs::msg::MapProjectorInfo::LOCAL) {
     ;  // do nothing
   } else {
     throw std::runtime_error(
diff --git a/system/default_ad_api/src/vehicle.cpp b/system/default_ad_api/src/vehicle.cpp
index 43efdb2adfaf8..fb434adbb0e40 100644
--- a/system/default_ad_api/src/vehicle.cpp
+++ b/system/default_ad_api/src/vehicle.cpp
@@ -146,7 +146,7 @@ void VehicleNode::publish_kinematics()
   vehicle_kinematics.twist.header = kinematic_state_msgs_->header;
   vehicle_kinematics.twist.header.frame_id = kinematic_state_msgs_->child_frame_id;
   vehicle_kinematics.twist.twist = kinematic_state_msgs_->twist;
-  if (map_projector_info_->projector_type == "MGRS") {
+  if (map_projector_info_->projector_type == MapProjectorInfo::MGRS) {
     lanelet::GPSPoint projected_gps_point = lanelet::projection::MGRSProjector::reverse(
       toBasicPoint3dPt(kinematic_state_msgs_->pose.pose.position), map_projector_info_->mgrs_grid);
     vehicle_kinematics.geographic_pose.header = kinematic_state_msgs_->header;
@@ -154,7 +154,7 @@ void VehicleNode::publish_kinematics()
     vehicle_kinematics.geographic_pose.position.latitude = projected_gps_point.lat;
     vehicle_kinematics.geographic_pose.position.longitude = projected_gps_point.lon;
     vehicle_kinematics.geographic_pose.position.altitude = projected_gps_point.ele;
-  } else if (map_projector_info_->projector_type == "LocalCartesianUTM") {
+  } else if (map_projector_info_->projector_type == MapProjectorInfo::LOCAL_CARTESIAN_UTM) {
     lanelet::GPSPoint position{
       map_projector_info_->map_origin.latitude, map_projector_info_->map_origin.longitude};
     lanelet::Origin origin{position};