diff --git a/product_category_tax/models/product_product.py b/product_category_tax/models/product_product.py
index 16c41a503..afc712d47 100644
--- a/product_category_tax/models/product_product.py
+++ b/product_category_tax/models/product_product.py
@@ -8,7 +8,7 @@ class ProductProduct(models.Model):
     _inherit = "product.product"
 
     @api.onchange("categ_id")
-    def onchange_categ_id(self):
+    def _onchange_categ_id_set_taxes(self):
         if self.categ_id:
             self.set_tax_from_category()
 
diff --git a/product_category_tax/models/product_template.py b/product_category_tax/models/product_template.py
index e8e838530..f950db002 100644
--- a/product_category_tax/models/product_template.py
+++ b/product_category_tax/models/product_template.py
@@ -10,7 +10,7 @@ class ProductTemplate(models.Model):
     taxes_updeatable_from_category = fields.Boolean(default=True)
 
     @api.onchange("categ_id")
-    def onchange_categ_id(self):
+    def _onchange_categ_id_set_taxes(self):
         if self.categ_id:
             self.set_tax_from_category()
 
diff --git a/product_category_tax/tests/test_product_category_tax.py b/product_category_tax/tests/test_product_category_tax.py
index 9d1d0b2b6..cfbe1a84f 100644
--- a/product_category_tax/tests/test_product_category_tax.py
+++ b/product_category_tax/tests/test_product_category_tax.py
@@ -52,8 +52,8 @@ class ProductCategoryTax(common.SavepointCase):
         self.product_test = self.product_obj.create(
             {"name": "TEST 01", "categ_id": test_categ.id, "list_price": 155.0}
         )
-        self.product_test.product_tmpl_id.onchange_categ_id()
-        self.assertEqual(self.product_test.supplier_taxes_id, self.tax_purchase)
+        self.product_test.product_tmpl_id._onchange_categ_id_set_taxes()
+        self.assertEquals(self.product_test.supplier_taxes_id, self.tax_purchase)
 
     def test_02_update_taxes(self):
         """Default update"""