diff --git a/Core/Inc/compute.h b/Core/Inc/compute.h
index 2eb1873..e42e823 100644
--- a/Core/Inc/compute.h
+++ b/Core/Inc/compute.h
@@ -24,6 +24,7 @@ typedef enum {
 	FAN4,
 	FAN5,
 	FAN6,
+	FANMAX
 } fan_select_t;
 
 /**
diff --git a/Core/Src/compute.c b/Core/Src/compute.c
index 3b060c4..5433eb6 100644
--- a/Core/Src/compute.c
+++ b/Core/Src/compute.c
@@ -128,7 +128,7 @@ bool compute_charger_connected()
 uint8_t compute_set_fan_speed(TIM_HandleTypeDef* pwmhandle, fan_select_t fan_select, uint8_t duty_cycle)
 {
 	assert(pwmhandle);
-	assert(fan_select < 6);
+	assert(fan_select < FANMAX);
 	assert(duty_cycle <= 100);
 	uint32_t CCR_value = 0;