diff --git a/odoo/addons/base/tests/test_translate.py b/odoo/addons/base/tests/test_translate.py
index c1820317c63..c5bc5f98ecc 100644
--- a/odoo/addons/base/tests/test_translate.py
+++ b/odoo/addons/base/tests/test_translate.py
@@ -1,10 +1,13 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
+from unittest.mock import patch
+
+from psycopg2 import IntegrityError
+
 from odoo.exceptions import AccessError, ValidationError
 from odoo.tools import mute_logger
 from odoo.tools.translate import quote, unquote, xml_translate, html_translate
 from odoo.tests.common import TransactionCase, BaseCase, new_test_user
-from psycopg2 import IntegrityError
 
 
 class TranslationToolsTestCase(BaseCase):
@@ -244,6 +247,28 @@ class TranslationToolsTestCase(BaseCase):
         self.assertEqual(result, source)
 
 
+class TestLanguageInstall(TransactionCase):
+    def test_language_install(self):
+        fr = self.env['res.lang'].with_context(active_test=False).search([('code', '=', 'fr_FR')])
+        self.assertTrue(fr)
+        wizard = self.env['base.language.install'].create({'lang_ids': fr.ids})
+        wizard.flush()
+
+        # running the wizard calls _load_module_terms() to load PO files
+        loaded = []
+
+        def _load_module_terms(self, modules, langs, overwrite=False):
+            loaded.append((modules, langs, overwrite))
+
+        with patch('odoo.addons.base.models.ir_translation.IrTranslation._load_module_terms', _load_module_terms):
+            wizard.lang_install()
+
+        # _load_module_terms is called once with lang='fr_FR' and overwrite=True
+        self.assertEqual(len(loaded), 1)
+        self.assertEqual(loaded[0][1], ['fr_FR'])
+        self.assertEqual(loaded[0][2], True)
+
+
 class TestTranslation(TransactionCase):
     @classmethod
     def setUpClass(cls):
diff --git a/odoo/addons/base/wizard/base_language_install.py b/odoo/addons/base/wizard/base_language_install.py
index 56ebe6b0a7d..e2bc605141f 100644
--- a/odoo/addons/base/wizard/base_language_install.py
+++ b/odoo/addons/base/wizard/base_language_install.py
@@ -36,13 +36,11 @@ class BaseLanguageInstall(models.TransientModel):
     def lang_install(self):
         self.ensure_one()
         mods = self.env['ir.module.module'].search([('state', '=', 'installed')])
-        lang_ids = self.lang_ids
-        langs_to_activate = lang_ids.filtered(lambda l: not l.active)
-        langs_to_activate.toggle_active()
-        mods._update_translations(lang_ids.mapped('code'), self.overwrite)
+        self.lang_ids.active = True
+        mods._update_translations(self.lang_ids.mapped('code'), self.overwrite)
         self.env.cr.execute('ANALYZE ir_translation')
 
-        if len(lang_ids) == 1:
+        if len(self.lang_ids) == 1:
             return {
                 'type': 'ir.actions.act_window',
                 'res_model': 'base.language.install',