diff --git a/Marlin/src/inc/Conditionals_post.h b/Marlin/src/inc/Conditionals_post.h
index 42379506ce..04e96177b5 100644
--- a/Marlin/src/inc/Conditionals_post.h
+++ b/Marlin/src/inc/Conditionals_post.h
@@ -2728,10 +2728,6 @@
   #define HAS_FAN 1
 #endif
 
-#ifndef FAN_INVERTING
-  #define FAN_INVERTING false
-#endif
-
 #if PIN_EXISTS(FANMUX0)
   #define HAS_FANMUX 1  // Part Cooling fan multipliexer
 #endif
diff --git a/Marlin/src/module/temperature.cpp b/Marlin/src/module/temperature.cpp
index fc9e08fe7c..afde7d3b34 100644
--- a/Marlin/src/module/temperature.cpp
+++ b/Marlin/src/module/temperature.cpp
@@ -370,9 +370,9 @@ PGMSTR(str_t_heating_failed, STR_T_HEATING_FAILED);
 
 // Init fans according to whether they're native PWM or Software PWM
 #ifdef BOARD_OPENDRAIN_MOSFETS
-  #define _INIT_SOFT_FAN(P) OUT_WRITE_OD(P, FAN_INVERTING ? LOW : HIGH)
+  #define _INIT_SOFT_FAN(P) OUT_WRITE_OD(P, ENABLED(FAN_INVERTING) ? LOW : HIGH)
 #else
-  #define _INIT_SOFT_FAN(P) OUT_WRITE(P, FAN_INVERTING ? LOW : HIGH)
+  #define _INIT_SOFT_FAN(P) OUT_WRITE(P, ENABLED(FAN_INVERTING) ? LOW : HIGH)
 #endif
 #if ENABLED(FAN_SOFT_PWM)
   #define _INIT_FAN_PIN(P) _INIT_SOFT_FAN(P)
@@ -3819,7 +3819,7 @@ void Temperature::isr() {
     static SoftPWM soft_pwm_controller;
   #endif
 
-  #define WRITE_FAN(n, v) WRITE(FAN##n##_PIN, (v) ^ FAN_INVERTING)
+  #define WRITE_FAN(n, v) WRITE(FAN##n##_PIN, (v) ^ ENABLED(FAN_INVERTING))
 
   #if DISABLED(SLOW_PWM_HEATERS)