diff --git a/lib/GazDisplay/GazDisplay.h b/lib/GazDisplay/GazDisplay.h
index 24ceadc..3b757fc 100644
--- a/lib/GazDisplay/GazDisplay.h
+++ b/lib/GazDisplay/GazDisplay.h
@@ -16,6 +16,6 @@ enum class DisplayError : int16_t {
     INIT_FAILED  = -1
 };
 
-void displayInit();
+DisplayError displayInit();
 void displayGasIndex(uint32_t pulses);