diff --git a/test/piston.jl b/test/piston.jl
index a6bd0985..7dccc85a 100644
--- a/test/piston.jl
+++ b/test/piston.jl
@@ -1,9 +1,12 @@
 using ModelingToolkit, Test
+using ModelingToolkitBase: @independent_variables
 using SciCompDSL
 using SciMLBase
 using ModelingToolkitStandardLibrary.Thermal
 using ModelingToolkitStandardLibrary.Blocks
 
+@independent_variables t
+
 # Tests ConvectiveResistor and includes FixedTemperature and ThermalResistor
 
 @testset "Piston cylinder wall" begin