diff --git a/ugv_sdk/CMakeLists.txt b/ugv_sdk/CMakeLists.txt
index 9214ffd..7b99562 100755
--- a/ugv_sdk/CMakeLists.txt
+++ b/ugv_sdk/CMakeLists.txt
@@ -91,8 +91,6 @@ add_library(${PROJECT_NAME}
     # src/scout_can_parser.c
     # src/scout_uart_parser.c
     src/tracer_base.cpp
-    # src/tracer_can_parser.c
-    # src/tracer_uart_parser.c
     # src/bunker_base.cpp
     # src/bunker_can_parser.c
 )
diff --git a/ugv_sdk/apps/tracer_demo/tracer_demo.cpp b/ugv_sdk/apps/tracer_demo/tracer_demo.cpp
index 732f3c8..5917473 100644
--- a/ugv_sdk/apps/tracer_demo/tracer_demo.cpp
+++ b/ugv_sdk/apps/tracer_demo/tracer_demo.cpp
@@ -32,23 +32,19 @@ int main(int argc, char **argv) {
 
   // light control
   std::cout << "Light: const off" << std::endl;
-  tracer.SetLightCommand({TracerLightCmd::LightMode::CONST_OFF, 0,
-                          TracerLightCmd::LightMode::CONST_OFF, 0});
+  tracer.SetLightCommand({TracerLightCmd::LightMode::CONST_OFF, 0});
   //   usleep(50000);
   sleep(3);
   std::cout << "Light: const on" << std::endl;
-  tracer.SetLightCommand({TracerLightCmd::LightMode::CONST_ON, 0,
-                          TracerLightCmd::LightMode::CONST_ON, 0});
+  tracer.SetLightCommand({TracerLightCmd::LightMode::CONST_ON, 0});
   //   usleep(50000);
   sleep(3);
   std::cout << "Light: breath" << std::endl;
-  tracer.SetLightCommand({TracerLightCmd::LightMode::BREATH, 0,
-                          TracerLightCmd::LightMode::BREATH, 0});
+  tracer.SetLightCommand({TracerLightCmd::LightMode::BREATH, 0});
   //   usleep(50000);
   sleep(8);
   std::cout << "Light: custom 90-80" << std::endl;
-  tracer.SetLightCommand({TracerLightCmd::LightMode::CUSTOM, 90,
-                          TracerLightCmd::LightMode::CUSTOM, 80});
+  tracer.SetLightCommand({TracerLightCmd::LightMode::CUSTOM, 90});
   //   usleep(50000);
   sleep(3);
   std::cout << "Light: diabled cmd control" << std::endl;
diff --git a/ugv_sdk/include/ugv_sdk/tracer/tracer_base.hpp b/ugv_sdk/include/ugv_sdk/tracer/tracer_base.hpp
index 3670af2..1bc9dd2 100644
--- a/ugv_sdk/include/ugv_sdk/tracer/tracer_base.hpp
+++ b/ugv_sdk/include/ugv_sdk/tracer/tracer_base.hpp
@@ -39,14 +39,10 @@ class TracerBase : public MobileBase {
  private:
   // cmd/status update related variables
   std::mutex tracer_state_mutex_;
-  std::mutex uart_tracer_state_mutex_;
   std::mutex motion_cmd_mutex_;
-  std::mutex light_cmd_mutex_;
-  std::mutex mode_cmd_mutex_;
 
   TracerState tracer_state_;
   TracerMotionCmd current_motion_cmd_;
-  TracerLightCmd current_light_cmd_;
 
   bool light_ctrl_enabled_ = false;
   bool light_ctrl_requested_ = false;
diff --git a/ugv_sdk/include/ugv_sdk/tracer/tracer_types.hpp b/ugv_sdk/include/ugv_sdk/tracer/tracer_types.hpp
index a898001..6a8e2c8 100644
--- a/ugv_sdk/include/ugv_sdk/tracer/tracer_types.hpp
+++ b/ugv_sdk/include/ugv_sdk/tracer/tracer_types.hpp
@@ -75,19 +75,14 @@ struct TracerLightCmd {
   };
 
   TracerLightCmd() = default;
-  TracerLightCmd(LightMode f_mode, uint8_t f_value, LightMode r_mode,
-                 uint8_t r_value)
-      : enable_ctrl(true),
-        front_mode(f_mode),
-        front_custom_value(f_value),
-        rear_mode(r_mode),
-        rear_custom_value(r_value) {}
+  TracerLightCmd(LightMode f_mode, uint8_t f_value)
+      : enable_ctrl(true), front_mode(f_mode), front_custom_value(f_value) {}
 
   bool enable_ctrl = false;
   LightMode front_mode;
   uint8_t front_custom_value;
-  LightMode rear_mode;
-  uint8_t rear_custom_value;
+  LightMode rear_mode = LightMode::CONST_OFF;
+  uint8_t rear_custom_value = 0;
 };
 }  // namespace westonrobot