diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
index 6db9d65b221c..1c942a4e4468 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
@@ -3980,8 +3980,8 @@ public void updateCodegenPropertyEnum(CodegenProperty var) {
         Map<String, Object> allowableValues = var.allowableValues;
 
         // handle array
-        if (var.items != null) {
-            allowableValues = var.items.allowableValues;
+        if (var.mostInnerItems != null) {
+            allowableValues = var.mostInnerItems.allowableValues;
         }
 
         if (allowableValues == null) {
@@ -3993,6 +3993,13 @@ public void updateCodegenPropertyEnum(CodegenProperty var) {
             return;
         }
 
+        String varDataType = var.mostInnerItems != null ? var.mostInnerItems.dataType : var.dataType;
+        Optional<Schema> referencedSchema = ModelUtils.getSchemas(openAPI).entrySet().stream()
+                .filter(entry -> Objects.equals(varDataType, toModelName(entry.getKey())))
+                .map(Map.Entry::getValue)
+                .findFirst();
+        String dataType = (referencedSchema.isPresent()) ? getTypeDeclaration(referencedSchema.get()) : varDataType;
+
         // put "enumVars" map into `allowableValues", including `name` and `value`
         List<Map<String, Object>> enumVars = new ArrayList<>();
         String commonPrefix = findCommonPrefixOfVars(values);
@@ -4009,7 +4016,6 @@ public void updateCodegenPropertyEnum(CodegenProperty var) {
                 }
             }
 
-            final String dataType = var.mostInnerItems != null ? var.mostInnerItems.dataType : var.dataType;
             enumVar.put("name", toEnumVarName(enumName, dataType));
             enumVar.put("value", toEnumValue(value.toString(), dataType));
             enumVar.put("isString", isDataTypeString(dataType));
@@ -4017,14 +4023,23 @@ public void updateCodegenPropertyEnum(CodegenProperty var) {
         }
         // if "x-enum-varnames" or "x-enum-descriptions" defined, update varnames
         Map<String, Object> extensions = var.mostInnerItems != null ? var.mostInnerItems.getVendorExtensions() : var.getVendorExtensions();
+        if(referencedSchema.isPresent()) {
+            extensions = referencedSchema.get().getExtensions();
+        }
         updateEnumVarsWithExtensions(enumVars, extensions);
         allowableValues.put("enumVars", enumVars);
 
         // handle default value for enum, e.g. available => StatusEnum.AVAILABLE
         if (var.defaultValue != null) {
             String enumName = null;
+            final String enumDefaultValue;
+            if("string".equalsIgnoreCase(dataType)) {
+                enumDefaultValue = toEnumValue(var.defaultValue, dataType);
+            } else {
+                enumDefaultValue = var.defaultValue;
+            }
             for (Map<String, Object> enumVar : enumVars) {
-                if (toEnumValue(var.defaultValue, var.dataType).equals(enumVar.get("value"))) {
+                if (enumDefaultValue.equals(enumVar.get("value"))) {
                     enumName = (String) enumVar.get("name");
                     break;
                 }
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java
index 348c41b1f830..c5f7d74284ff 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java
@@ -569,7 +569,8 @@ private CodegenProperty codegenPropertyWithArrayOfIntegerValues() {
         allowableValues.put("values", Collections.singletonList(1));
         items.setAllowableValues(allowableValues);
         items.dataType = "Integer";
-        array.setItems(items);
+        array.items = items;
+        array.mostInnerItems = items;
         array.dataType = "Array";
         return array;
     }