diff --git a/admin/tool/analytics/classes/output/models_list.php b/admin/tool/analytics/classes/output/models_list.php
index 0e8d4e8d61d..cbd0a60770d 100644
--- a/admin/tool/analytics/classes/output/models_list.php
+++ b/admin/tool/analytics/classes/output/models_list.php
@@ -119,6 +119,9 @@ class models_list implements \renderable, \templatable {
                     debugging("The time splitting method '{$modeldata->timesplitting}' should include a '{$identifier}_help'
                         string to describe its purpose.", DEBUG_DEVELOPER);
                 }
+            } else {
+                $helpicon = new \help_icon('timesplittingnotdefined', 'tool_analytics');
+                $modeldata->timesplittinghelp = $helpicon->export_for_template($output);
             }
 
             // Has this model generated predictions?.
@@ -207,19 +210,22 @@ class models_list implements \renderable, \templatable {
             }
 
             // Enable / disable.
-            if ($model->is_enabled()) {
-                $action = 'disable';
-                $text = get_string('disable');
-                $icontype = 't/block';
-            } else {
-                $action = 'enable';
-                $text = get_string('enable');
-                $icontype = 'i/checked';
+            if ($model->is_enabled() || !empty($modeldata->timesplitting)) {
+                // If there is no timesplitting method set, the model can not be enabled.
+                if ($model->is_enabled()) {
+                    $action = 'disable';
+                    $text = get_string('disable');
+                    $icontype = 't/block';
+                } else {
+                    $action = 'enable';
+                    $text = get_string('enable');
+                    $icontype = 'i/checked';
+                }
+                $urlparams['action'] = $action;
+                $url = new \moodle_url('model.php', $urlparams);
+                $icon = new \action_menu_link_secondary($url, new \pix_icon($icontype, $text), $text);
+                $actionsmenu->add($icon);
             }
-            $urlparams['action'] = $action;
-            $url = new \moodle_url('model.php', $urlparams);
-            $icon = new \action_menu_link_secondary($url, new \pix_icon($icontype, $text), $text);
-            $actionsmenu->add($icon);
 
             // Export training data.
             if (!$model->is_static() && $model->is_trained()) {
diff --git a/admin/tool/analytics/lang/en/tool_analytics.php b/admin/tool/analytics/lang/en/tool_analytics.php
index f5c1014e8a3..157eee64df9 100644
--- a/admin/tool/analytics/lang/en/tool_analytics.php
+++ b/admin/tool/analytics/lang/en/tool_analytics.php
@@ -83,6 +83,8 @@ $string['previouspage'] = 'Previous page';
 $string['samestartdate'] = 'Current start date is good';
 $string['sameenddate'] = 'Current end date is good';
 $string['target'] = 'Target';
+$string['timesplittingnotdefined'] = 'Time splitting is not defined.';
+$string['timesplittingnotdefined_help'] = 'You need to select a time-splitting method before enabling the model.';
 $string['trainandpredictmodel'] = 'Training model and calculating predictions';
 $string['trainingprocessfinished'] = 'Training process finished';
 $string['trainingresults'] = 'Training results';
diff --git a/admin/tool/analytics/templates/models_list.mustache b/admin/tool/analytics/templates/models_list.mustache
index 8eb6211a138..efdc4cabab5 100644
--- a/admin/tool/analytics/templates/models_list.mustache
+++ b/admin/tool/analytics/templates/models_list.mustache
@@ -160,6 +160,9 @@
                     {{/timesplitting}}
                     {{^timesplitting}}
                         {{#str}}notdefined, tool_analytics{{/str}}
+                        {{#timesplittinghelp}}
+                            {{>core/help_icon}}
+                        {{/timesplittinghelp}}
                     {{/timesplitting}}
                 </td>
                 <td>
diff --git a/analytics/classes/model.php b/analytics/classes/model.php
index d8816458511..0bee65002ca 100644
--- a/analytics/classes/model.php
+++ b/analytics/classes/model.php
@@ -1013,6 +1013,10 @@ class model {
             if (!$this->is_static()) {
                 $this->model->trained = 0;
             }
+        } else if (empty($this->model->timesplitting)) {
+            // A valid timesplitting method needs to be supplied before a model can be enabled.
+            throw new \moodle_exception('invalidtimesplitting', 'analytics', '', $this->model->id);
+
         }
 
         // Purge pages with insights as this may change things.
diff --git a/analytics/tests/model_test.php b/analytics/tests/model_test.php
index 2685b64bbcb..d5d0153e9ac 100644
--- a/analytics/tests/model_test.php
+++ b/analytics/tests/model_test.php
@@ -226,7 +226,7 @@ class analytics_model_testcase extends advanced_testcase {
         $this->model->mark_as_trained();
         $this->assertEquals($originaluniqueid, $this->model->get_unique_id());
 
-        $this->model->enable();
+        $this->model->enable('\core\analytics\time_splitting\deciles');
         $this->assertEquals($originaluniqueid, $this->model->get_unique_id());
 
         // Wait 1 sec so the timestamp changes.