diff --git a/tests/model/mseed_data/test_mseed.py b/tests/model/mseed_data/test_mseed.py
index c3cec5908d1a9a8064d5c2924366fe866ad4429f..50af120b87f2f78c2c0722e7aa384cb35f733911 100644
--- a/tests/model/mseed_data/test_mseed.py
+++ b/tests/model/mseed_data/test_mseed.py
@@ -344,7 +344,7 @@ class TestMSeed(BaseTestCase):
             'list_of_dir': [q330_data],
             'req_soh_chans': [],
             'req_wf_chans': [],
-            'include_mp123zne': True
+            'include_mp123uvw': True
         }
         obj = MSeed(**args)
         self.assertEqual(list(obj.mass_pos_data.keys()), ['AX08'])
diff --git a/tests/model/mseed_data/test_mseed_reader.py b/tests/model/mseed_data/test_mseed_reader.py
index 52cea0835beda45b804dddc25b07b1872badf527..113730a00761e454e86afd90a3a7d60f05c036bc 100644
--- a/tests/model/mseed_data/test_mseed_reader.py
+++ b/tests/model/mseed_data/test_mseed_reader.py
@@ -244,7 +244,7 @@ class TestMSeedReader(BaseTestCase):
         args = {
             'file_path': mass_pos_file,
             'is_multiplex': False,
-            'include_mp123zne': True,
+            'include_mp123uvw': True,
             'soh_data': self.soh_data,
             'mass_pos_data': self.mass_pos_data,
             'waveform_data': self.waveform_data,
diff --git a/tests/model/reftek_data/test_reftek.py b/tests/model/reftek_data/test_reftek.py
index 16c8603f3ec873a625ef6fef7136f45bb0f4959e..1012adf2cf83801242ee3c72a6f417633ed7f493 100644
--- a/tests/model/reftek_data/test_reftek.py
+++ b/tests/model/reftek_data/test_reftek.py
@@ -109,7 +109,7 @@ class TestReftek(BaseTestCase):
             'data_type': 'RT130',
             'list_of_dir': [reftek_data],
             'req_soh_chans': ['_'],
-            'include_mp123zne': True,
+            'include_mp123uvw': True,
             'rt130_waveform_data_req': False,
             'on_unittest': True
         }
diff --git a/tests/view/util/test_functions.py b/tests/view/util/test_functions.py
index 12e6b95c331c0e2a08e3ec19f060cfb1cad6200c..71fc0035e73b881163ccf4961a1cff7d7ac19a57 100644
--- a/tests/view/util/test_functions.py
+++ b/tests/view/util/test_functions.py
@@ -395,38 +395,30 @@ class TestCheckMassPos(BaseTestCase):
                               include_mp123=True, include_mp456=False)
             self.assertEqual(
                 str(context.exception),
-                f"Data set {self.sel_key} doesn't include mass position 2")
-        with self.subTest("Consist of  MP1,MP3,MPE"):
+                f"Did not find mass-position channel(s) 2 in data set "
+                f"{self.sel_key}.")
+        with self.subTest("Consist of  MP1,MP3,MPV"):
             mp_data = {'MP1': {'chan_id': 'MP1', 'samplerate': 1},
                        'MP3': {'chan_id': 'MP3', 'samplerate': 1},
-                       'MPE': {'chan_id': 'MPE', 'samplerate': 1},
+                       'MPV': {'chan_id': 'MPV', 'samplerate': 1},
                        'MP4': {'chan_id': 'MP4', 'samplerate': 1}}
             with self.assertRaises(Exception) as context:
                 check_masspos(mp_data, self.sel_key,
                               include_mp123=True, include_mp456=False)
             self.assertEqual(
                 str(context.exception),
-                f"Data set {self.sel_key} doesn't include mass position "
-                f"2,Z,N")
-        with self.subTest("Consist of MPB"):
-            mp_data = {'MPB': {'chan_id': 'MPB', 'samplerate': 1},
-                       'MP4': {'chan_id': 'MP4', 'samplerate': 1}}
-            with self.assertRaises(Exception) as context:
-                check_masspos(mp_data, self.sel_key,
-                              include_mp123=True, include_mp456=False)
-            self.assertEqual(
-                str(context.exception),
-                f"Data set {self.sel_key} doesn't include mass position "
-                f"A,C")
-        with self.subTest("No MP 123/ZNE/ABC"):
+                f"Did not find mass-position channel(s) 2, U, W in data set "
+                f"{self.sel_key}.")
+
+        with self.subTest("No MP 123/UVW"):
             mp_data = {'MP4': {'chan_id': 'MP4', 'samplerate': 1}}
             with self.assertRaises(Exception) as context:
                 check_masspos(mp_data, self.sel_key,
                               include_mp123=True, include_mp456=False)
             self.assertEqual(
                 str(context.exception),
-                f"Data set {self.sel_key} doesn't include mass position "
-                f"1,2,3")
+                f"Did not find mass-position channel(s) 123/UVW in data set "
+                f"{self.sel_key}.")
 
     def test_include_mp456_not_include456(self):
         with self.subTest("Consist of MP4"):
@@ -437,25 +429,27 @@ class TestCheckMassPos(BaseTestCase):
                               include_mp123=False, include_mp456=True)
             self.assertEqual(
                 str(context.exception),
-                f"Data set {self.sel_key} doesn't include mass position 5,6")
+                f"Did not find mass-position channel(s) 5, 6 in data set "
+                f"{self.sel_key}.")
         with self.subTest("Consist of MPW"):
             mp_data = {'MP1': {'chan_id': 'MP1', 'samplerate': 1},
-                       'MPW': {'chan_id': 'MPW', 'samplerate': 1}}
+                       'MPZ': {'chan_id': 'MPZ', 'samplerate': 1}}
             with self.assertRaises(Exception) as context:
                 check_masspos(mp_data, self.sel_key,
                               include_mp123=False, include_mp456=True)
             self.assertEqual(
                 str(context.exception),
-                f"Data set {self.sel_key} doesn't include mass position U,V")
-        with self.subTest("No MP 456/UVW"):
+                f"Did not find mass-position channel(s) N, E in data set "
+                f"{self.sel_key}.")
+        with self.subTest("No MP 456/ZNE"):
             mp_data = {'MP1': {'chan_id': 'MP1', 'samplerate': 1}}
             with self.assertRaises(Exception) as context:
                 check_masspos(mp_data, self.sel_key,
                               include_mp123=False, include_mp456=True)
             self.assertEqual(
                 str(context.exception),
-                f"Data set {self.sel_key} doesn't include mass position "
-                f"4,5,6")
+                f"Did not find mass-position channel(s) 456/ZNE in data set "
+                f"{self.sel_key}.")
 
     def test_include_mp123456(self):
         mp_data = {'MP1': {'chan_id': 'MP1', 'samplerate': 1},
@@ -466,7 +460,8 @@ class TestCheckMassPos(BaseTestCase):
                           include_mp123=True, include_mp456=True)
         self.assertEqual(
             str(context.exception),
-            f"Data set {self.sel_key} doesn't include mass position 2,5,6")
+            f"Did not find mass-position channel(s) 2, 5, 6 in data set "
+            f"{self.sel_key}.")
 
     def test_not_include_mp(self):
         mp_data = {'MP1': {'chan_id': 'MP1', 'samplerate': 1},