diff --git a/firmware/controllers/algo/shift_torque_reduction_controller.cpp b/firmware/controllers/algo/shift_torque_reduction_controller.cpp
index 5bbb6b2e4f..24716eaaa4 100644
--- a/firmware/controllers/algo/shift_torque_reduction_controller.cpp
+++ b/firmware/controllers/algo/shift_torque_reduction_controller.cpp
@@ -19,6 +19,9 @@ void ShiftTorqueReductionController::update() {
 		updateTimeConditionSatisfied();
         updateRpmConditionSatisfied();
         updateAppConditionSatisfied();
+
+        isFlatShiftConditionSatisfied = torqueReductionTriggerPinState && isTimeConditionSatisfied
+            && isRpmConditionSatisfied && isAppConditionSatisfied;
     }
 }
 
diff --git a/firmware/controllers/algo/shift_torque_reduction_state.txt b/firmware/controllers/algo/shift_torque_reduction_state.txt
index 1a9eb30d3b..b88ddecd17 100644
--- a/firmware/controllers/algo/shift_torque_reduction_state.txt
+++ b/firmware/controllers/algo/shift_torque_reduction_state.txt
@@ -5,5 +5,6 @@ bit torqueReductionTriggerPinState
 bit isTimeConditionSatisfied
 bit isRpmConditionSatisfied
 bit isAppConditionSatisfied
+bit isFlatShiftConditionSatisfied
 
 end_struct
diff --git a/unit_tests/tests/shift_torque_reduction/test_shift_torque_reduction_flat_shift_condition.cpp b/unit_tests/tests/shift_torque_reduction/test_shift_torque_reduction_flat_shift_condition.cpp
new file mode 100644
index 0000000000..6de50d375c
--- /dev/null
+++ b/unit_tests/tests/shift_torque_reduction/test_shift_torque_reduction_flat_shift_condition.cpp
@@ -0,0 +1,112 @@
+//
+// Created by kifir on 10/4/24.
+//
+
+#include "pch.h"
+
+#include "shift_torque_reduction_test_base.h"
+
+namespace {
+    class ShiftTorqueReductionFlatShiftConditionTest : public ShiftTorqueReductionTestBase {
+    protected:
+        static constexpr switch_input_pin_e TEST_TORQUE_REDUCTION_BUTTON_PIN = Gpio::E13;
+        static constexpr float TEST_TORQUE_REDUCTION_TIME = 123.45f;
+        static constexpr float TEST_TORQUE_REDUCTION_ARMING_RPM = 678.90f;
+        static constexpr float TEST_TORQUE_REDUCTION_ARMING_APP = 12.3f;
+        static constexpr float IMMEDIATELY = 0.0f;
+
+        void SetUp() override;
+
+        void triggerPin();
+        void satisfyRpmCondition();
+        void satisfyAppCondition();
+
+        void waitAndCheckFlatShiftCondition(float timeoutInMs, bool expectedFlatShiftCondition, const char* context);
+    };
+
+    void ShiftTorqueReductionFlatShiftConditionTest::SetUp() {
+        TestBase::SetUp();
+        setUpTestConfig(ShiftTorqueReductionTestConfig()
+            .setTorqueReductionEnabled(true)
+            .setTorqueReductionActivationMode(torqueReductionActivationMode_e::TORQUE_REDUCTION_BUTTON)
+            .setTriggerPin(TEST_TORQUE_REDUCTION_BUTTON_PIN)
+            .setTorqueReductionTime(TEST_TORQUE_REDUCTION_TIME)
+            .setTorqueReductionArmingRpm(TEST_TORQUE_REDUCTION_ARMING_RPM)
+            .setTorqueReductionArmingApp(TEST_TORQUE_REDUCTION_ARMING_APP)
+        );
+    }
+
+    void ShiftTorqueReductionFlatShiftConditionTest::triggerPin() {
+        setMockState(TEST_TORQUE_REDUCTION_BUTTON_PIN, true);
+        periodicFastCallback();
+        EXPECT_TRUE(engine->shiftTorqueReductionController.isTorqueReductionTriggerPinValid);
+        EXPECT_TRUE(engine->shiftTorqueReductionController.torqueReductionTriggerPinState);
+        EXPECT_TRUE(engine->shiftTorqueReductionController.isTimeConditionSatisfied);
+    }
+
+    void ShiftTorqueReductionFlatShiftConditionTest::satisfyRpmCondition() {
+        updateRpm(TEST_TORQUE_REDUCTION_ARMING_RPM);
+        EXPECT_TRUE(engine->shiftTorqueReductionController.isRpmConditionSatisfied);
+    }
+
+    void ShiftTorqueReductionFlatShiftConditionTest::satisfyAppCondition() {
+        updateApp(TEST_TORQUE_REDUCTION_ARMING_APP);
+        EXPECT_TRUE(engine->shiftTorqueReductionController.isAppConditionSatisfied);
+    }
+
+    void ShiftTorqueReductionFlatShiftConditionTest::waitAndCheckFlatShiftCondition(
+        const float timeoutInMs,
+        const bool expectedFlatShiftCondition,
+        const char* const context
+    ) {
+        advanceTimeUs(MS2US(timeoutInMs));
+        periodicFastCallback();
+        EXPECT_EQ(engine->shiftTorqueReductionController.isFlatShiftConditionSatisfied, expectedFlatShiftCondition)
+            << context;
+    }
+
+    TEST_F(ShiftTorqueReductionFlatShiftConditionTest, checkSatisfiedFlatShiftCondition) {
+        triggerPin();
+        satisfyRpmCondition();
+        satisfyAppCondition();
+        waitAndCheckFlatShiftCondition(IMMEDIATELY, true, "App condition is satisfied");
+    }
+
+    TEST_F(ShiftTorqueReductionFlatShiftConditionTest, checkWithoutTriggeredPin) {
+        //triggerPin();
+        satisfyRpmCondition();
+        satisfyAppCondition();
+        waitAndCheckFlatShiftCondition(IMMEDIATELY, false, "Without triggered pin");
+    }
+
+    TEST_F(ShiftTorqueReductionFlatShiftConditionTest, checkWithoutRpmCondition) {
+        triggerPin();
+        //satisfyRpmCondition();
+        satisfyAppCondition();
+        waitAndCheckFlatShiftCondition(IMMEDIATELY, false, "Without rpm condition");
+    }
+
+    TEST_F(ShiftTorqueReductionFlatShiftConditionTest, checkWithoutAppCondition) {
+        triggerPin();
+        satisfyRpmCondition();
+        //satisfyAppCondition();
+        waitAndCheckFlatShiftCondition(IMMEDIATELY, false, "Without app condition");
+    }
+
+    TEST_F(ShiftTorqueReductionFlatShiftConditionTest, checkSatisfiedFlatShiftConditionExpiration) {
+        waitAndCheckFlatShiftCondition(IMMEDIATELY, false, "Default");
+
+        triggerPin();
+        waitAndCheckFlatShiftCondition(IMMEDIATELY, false, "Time condition is satisfied");
+
+        satisfyRpmCondition();
+        waitAndCheckFlatShiftCondition(IMMEDIATELY, false, "Rpm condition is satisfied");
+
+        satisfyAppCondition();
+        waitAndCheckFlatShiftCondition(IMMEDIATELY, true, "App condition is satisfied");
+
+        waitAndCheckFlatShiftCondition(TEST_TORQUE_REDUCTION_TIME, true, "Flat shift condition is still satisfied");
+
+        waitAndCheckFlatShiftCondition(EPS3D, false, "Flat shift condition is expired");
+    }
+}
\ No newline at end of file
diff --git a/unit_tests/tests/tests.mk b/unit_tests/tests/tests.mk
index cc96afe318..2e29a6e0cf 100644
--- a/unit_tests/tests/tests.mk
+++ b/unit_tests/tests/tests.mk
@@ -62,6 +62,7 @@ TESTS_SRC_CPP = \
 	tests/shift_torque_reduction/test_shift_torque_reduction_time_condition.cpp \
 	tests/shift_torque_reduction/test_shift_torque_reduction_rpm_condition.cpp \
 	tests/shift_torque_reduction/test_shift_torque_reduction_app_condition.cpp \
+	tests/shift_torque_reduction/test_shift_torque_reduction_flat_shift_condition.cpp \
 	tests/lua/test_lua_basic.cpp \
 	tests/lua/test_lookup.cpp \
 	tests/lua/test_lua_e38.cpp \