diff --git a/src/drivers/l3gd20/l3gd20.cpp b/src/drivers/l3gd20/l3gd20.cpp
index 4e2f198b8a..08bc1fead8 100644
--- a/src/drivers/l3gd20/l3gd20.cpp
+++ b/src/drivers/l3gd20/l3gd20.cpp
@@ -1137,6 +1137,7 @@ void	test();
 void	reset();
 void	info();
 void	regdump();
+void	test_error();
 
 /**
  * Start the driver.