diff --git a/lib/turbo/engine.rb b/lib/turbo/engine.rb
index dc7e0853..b82c775d 100644
--- a/lib/turbo/engine.rb
+++ b/lib/turbo/engine.rb
@@ -81,10 +81,13 @@ class Engine < Rails::Engine
     initializer "turbo.test_assertions" do
       ActiveSupport.on_load(:active_support_test_case) do
         require "turbo/test_assertions"
-        require "turbo/broadcastable/test_helper"
 
         include Turbo::TestAssertions
-        include Turbo::Broadcastable::TestHelper
+
+        if defined? ActionCable
+          require "turbo/broadcastable/test_helper"
+          include Turbo::Broadcastable::TestHelper
+        end
       end
 
       ActiveSupport.on_load(:action_dispatch_integration_test) do