From 0f5d45725252294d5a6aad8ca30ab2f7d64741d7 Mon Sep 17 00:00:00 2001
From: Giuliano Zaro <3684609+GMagician@users.noreply.github.com>
Date: Thu, 24 Oct 2019 19:23:06 +0200
Subject: [PATCH] Allow redundant temp sensor with SINGLENOZZLE (#15650)

---
 Marlin/src/inc/Conditionals_LCD.h | 1 -
 Marlin/src/inc/SanityCheck.h      | 6 ++----
 2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/Marlin/src/inc/Conditionals_LCD.h b/Marlin/src/inc/Conditionals_LCD.h
index 2987a1e0a..81d7cec30 100644
--- a/Marlin/src/inc/Conditionals_LCD.h
+++ b/Marlin/src/inc/Conditionals_LCD.h
@@ -416,7 +416,6 @@
 #if EITHER(SINGLENOZZLE, MIXING_EXTRUDER)         // One hotend, one thermistor, no XY offset
   #undef HOTENDS
   #define HOTENDS       1
-  #undef TEMP_SENSOR_1_AS_REDUNDANT
   #undef HOTEND_OFFSET_X
   #undef HOTEND_OFFSET_Y
 #endif
diff --git a/Marlin/src/inc/SanityCheck.h b/Marlin/src/inc/SanityCheck.h
index 1cbb09df0..b76cf5881 100644
--- a/Marlin/src/inc/SanityCheck.h
+++ b/Marlin/src/inc/SanityCheck.h
@@ -743,10 +743,6 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
     #error "Marlin supports a maximum of 6 EXTRUDERS."
   #endif
 
-  #if ENABLED(TEMP_SENSOR_1_AS_REDUNDANT)
-    #error "EXTRUDERS must be 1 with TEMP_SENSOR_1_AS_REDUNDANT."
-  #endif
-
   #if ENABLED(HEATERS_PARALLEL)
     #error "EXTRUDERS must be 1 with HEATERS_PARALLEL."
   #endif
@@ -1501,6 +1497,8 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
     #error "TEMP_SENSOR_1 is required with 2 or more HOTENDS."
   #elif !ANY_PIN(TEMP_1, MAX6675_SS2)
     #error "TEMP_1_PIN not defined for this board."
+  #elif ENABLED(TEMP_SENSOR_1_AS_REDUNDANT)
+    #error "HOTENDS must be 1 with TEMP_SENSOR_1_AS_REDUNDANT."
   #endif
   #if HOTENDS > 2
     #if TEMP_SENSOR_2 == 0