diff --git a/java_tools/ConfigDefinition.jar b/java_tools/ConfigDefinition.jar
index 73c58e6f1d..34e2d03826 100644
Binary files a/java_tools/ConfigDefinition.jar and b/java_tools/ConfigDefinition.jar differ
diff --git a/java_tools/configuration_definition/src/main/java/com/rusefi/output/TsOutput.java b/java_tools/configuration_definition/src/main/java/com/rusefi/output/TsOutput.java
index 5fedc02132..fba47bcde7 100644
--- a/java_tools/configuration_definition/src/main/java/com/rusefi/output/TsOutput.java
+++ b/java_tools/configuration_definition/src/main/java/com/rusefi/output/TsOutput.java
@@ -5,6 +5,8 @@ import com.rusefi.ConfigField;
 import com.rusefi.ReaderState;
 import com.rusefi.TypesHelper;
 
+import java.util.TreeSet;
+
 import static com.rusefi.ToolUtil.EOL;
 import static com.rusefi.output.JavaSensorsConsumer.quote;
 
@@ -19,6 +21,7 @@ public class TsOutput {
     private final StringBuilder settingContextHelp = new StringBuilder();
     private final boolean isConstantsSection;
     private final StringBuilder tsHeader = new StringBuilder();
+    private final TreeSet<String> usedNames = new TreeSet<>(String.CASE_INSENSITIVE_ORDER);
 
     public TsOutput(boolean longForm) {
         this.isConstantsSection = longForm;
@@ -41,6 +44,14 @@ public class TsOutput {
                 int bitIndex = it.bitState.get();
                 String nameWithPrefix = prefix + configField.getName();
 
+                /**
+                 * in 'Constants' section we have conditional sections and this check is not smart enough to handle those right
+                 * A simple solution would be to allow only one variable per each conditional section - would be simpler not to check against previous field
+                 */
+                if (!usedNames.add(nameWithPrefix) && !isConstantsSection) {
+                    throw new IllegalStateException(nameWithPrefix + " already present");
+                }
+
                 if (configField.getName().startsWith(ConfigStructure.ALIGNMENT_FILL_AT)) {
                     tsPosition += configField.getSize(next);
                     return tsPosition;
diff --git a/java_tools/configuration_definition/src/test/java/com/rusefi/test/OutputsTest.java b/java_tools/configuration_definition/src/test/java/com/rusefi/test/OutputsTest.java
index bdc63ae02e..7fd2632531 100644
--- a/java_tools/configuration_definition/src/test/java/com/rusefi/test/OutputsTest.java
+++ b/java_tools/configuration_definition/src/test/java/com/rusefi/test/OutputsTest.java
@@ -201,7 +201,7 @@ public class OutputsTest {
                         "\ttriggerSimulatorPins3 = \"Each rusEFI piece can provide synthetic trigger signal for external ECU. Sometimes these wires are routed back into trigger inputs of the same rusEFI board.\"\n", tsProjectConsumer.getSettingContextHelp().toString());
     }
 
-    @Test
+    @Test(expected = IllegalStateException.class)
     public void nameDuplicate() {
         String test = "struct total\n" +
                 "float afr_type;PID dTime;\"ms\",      1,      0,       0, 3000,      0\n" +