diff --git a/Marlin/src/inc/Conditionals_post.h b/Marlin/src/inc/Conditionals_post.h
index a5a1070b03b4..eb215c34ebe1 100644
--- a/Marlin/src/inc/Conditionals_post.h
+++ b/Marlin/src/inc/Conditionals_post.h
@@ -526,84 +526,91 @@
 #undef ANY_TEMP_SENSOR_IS
 
 // Usurp a sensor to do redundant readings
-#if TEMP_SENSOR_REDUNDANT && !PIN_EXISTS(TEMP_REDUNDANT)
-  #if TEMP_SENSOR_REDUNDANT_SOURCE == -5
-    #if !PIN_EXISTS(TEMP_COOLER)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to COOLER requires TEMP_COOLER_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_COOLER_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == -4
-    #if !PIN_EXISTS(TEMP_PROBE)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to PROBE requires TEMP_PROBE_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_PROBE_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == -2
-    #if !PIN_EXISTS(TEMP_CHAMBER)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to CHAMBER requires TEMP_CHAMBER_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_CHAMBER_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == -1
-    #if !PIN_EXISTS(TEMP_BED)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to BED requires TEMP_BED_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_BED_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == 0
-    #if !PIN_EXISTS(TEMP_0)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 0 requires TEMP_0_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_0_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == 1
-    #if !PIN_EXISTS(TEMP_1)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 1 requires TEMP_1_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_1_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == 2
-    #if !PIN_EXISTS(TEMP_2)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 2 requires TEMP_2_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_2_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == 3
-    #if !PIN_EXISTS(TEMP_3)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 3 requires TEMP_3_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_3_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == 4
-    #if !PIN_EXISTS(TEMP_4)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 4 requires TEMP_4_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_4_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == 5
-    #if !PIN_EXISTS(TEMP_5)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 5 requires TEMP_5_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_5_PIN
-    #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == 6
-    #if !PIN_EXISTS(TEMP_6)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 6 requires TEMP_6_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_6_PIN
+#if TEMP_SENSOR_REDUNDANT
+  #ifndef TEMP_SENSOR_REDUNDANT_SOURCE
+    #define TEMP_SENSOR_REDUNDANT_SOURCE 1
+  #endif
+  #ifndef TEMP_SENSOR_REDUNDANT_TARGET
+    #define TEMP_SENSOR_REDUNDANT_TARGET 0
+  #endif
+  #if !PIN_EXISTS(TEMP_REDUNDANT)
+    #ifndef TEMP_SENSOR_REDUNDANT_MAX_DIFF
+      #define TEMP_SENSOR_REDUNDANT_MAX_DIFF 10
     #endif
-  #elif TEMP_SENSOR_REDUNDANT_SOURCE == 7
-    #if !PIN_EXISTS(TEMP_7)
-      #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 7 requires TEMP_7_PIN."
-    #else
-      #define TEMP_REDUNDANT_PIN TEMP_7_PIN
+    #if TEMP_SENSOR_REDUNDANT_SOURCE == -5
+      #if !PIN_EXISTS(TEMP_COOLER)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to COOLER requires TEMP_COOLER_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_COOLER_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == -4
+      #if !PIN_EXISTS(TEMP_PROBE)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to PROBE requires TEMP_PROBE_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_PROBE_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == -2
+      #if !PIN_EXISTS(TEMP_CHAMBER)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to CHAMBER requires TEMP_CHAMBER_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_CHAMBER_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == -1
+      #if !PIN_EXISTS(TEMP_BED)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to BED requires TEMP_BED_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_BED_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == 0
+      #if !PIN_EXISTS(TEMP_0)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 0 requires TEMP_0_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_0_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == 1
+      #if !PIN_EXISTS(TEMP_1)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 1 requires TEMP_1_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_1_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == 2
+      #if !PIN_EXISTS(TEMP_2)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 2 requires TEMP_2_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_2_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == 3
+      #if !PIN_EXISTS(TEMP_3)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 3 requires TEMP_3_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_3_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == 4
+      #if !PIN_EXISTS(TEMP_4)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 4 requires TEMP_4_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_4_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == 5
+      #if !PIN_EXISTS(TEMP_5)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 5 requires TEMP_5_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_5_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == 6
+      #if !PIN_EXISTS(TEMP_6)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 6 requires TEMP_6_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_6_PIN
+      #endif
+    #elif TEMP_SENSOR_REDUNDANT_SOURCE == 7
+      #if !PIN_EXISTS(TEMP_7)
+        #error "TEMP_SENSOR_REDUNDANT_SOURCE set to 7 requires TEMP_7_PIN."
+      #else
+        #define TEMP_REDUNDANT_PIN TEMP_7_PIN
+      #endif
     #endif
   #endif
-
-  #ifndef TEMP_SENSOR_REDUNDANT_MAX_DIFF
-    #define TEMP_SENSOR_REDUNDANT_MAX_DIFF 10
-  #endif
 #endif
 
 #if TEMP_SENSOR_0 == -5 || TEMP_SENSOR_0 == -3 || TEMP_SENSOR_0 == -2
diff --git a/Marlin/src/module/temperature.cpp b/Marlin/src/module/temperature.cpp
index 9274d0631e99..9f32ce933bff 100644
--- a/Marlin/src/module/temperature.cpp
+++ b/Marlin/src/module/temperature.cpp
@@ -2090,16 +2090,30 @@ void Temperature::init() {
   #endif
 
   #if HAS_MAX31865_TEMP
-    TERN_(TEMP_SENSOR_IS_MAX(0, MAX31865), max31865_0.begin(MAX31865_2WIRE)); // MAX31865_2WIRE, MAX31865_3WIRE, MAX31865_4WIRE
-    TERN_(TEMP_SENSOR_IS_MAX(1, MAX31865), max31865_1.begin(MAX31865_2WIRE));
+    #if TEMP_SENSOR_IS_MAX(0, MAX31865)
+      max31865_0.begin(MAX31865_2WIRE); // MAX31865_2WIRE, MAX31865_3WIRE, MAX31865_4WIRE
+    #endif
+    #if TEMP_SENSOR_IS_MAX(1, MAX31865)
+      max31865_1.begin(MAX31865_2WIRE);
+    #endif
   #endif
+
   #if HAS_MAX31855_TEMP
-    TERN_(TEMP_SENSOR_IS_MAX(0, MAX31855), max31855_0.begin());
-    TERN_(TEMP_SENSOR_IS_MAX(1, MAX31855), max31855_1.begin());
+    #if TEMP_SENSOR_IS_MAX(0, MAX31855)
+      max31855_0.begin(MAX31855);
+    #endif
+    #if TEMP_SENSOR_IS_MAX(1, MAX31855)
+      max31855_1.begin(MAX31855);
+    #endif
   #endif
+
   #if HAS_MAX6675_TEMP
-    TERN_(TEMP_SENSOR_IS_MAX(0, MAX6675), max6675_0.begin());
-    TERN_(TEMP_SENSOR_IS_MAX(1, MAX6675), max6675_1.begin());
+    #if TEMP_SENSOR_IS_MAX(0, MAX6675)
+      max6675_0.begin(MAX6675);
+    #endif
+    #if TEMP_SENSOR_IS_MAX(1, MAX6675)
+      max6675_1.begin(MAX6675);
+    #endif
   #endif
 
   #if MB(RUMBA)