diff --git a/Marlin/temperature.cpp b/Marlin/temperature.cpp
index a494e3a9d..7bf0b6e53 100644
--- a/Marlin/temperature.cpp
+++ b/Marlin/temperature.cpp
@@ -188,7 +188,7 @@ static void updateTemperaturesFromRawValues();
 #endif
 
 //===========================================================================
-//================================ functions ================================
+//================================ Functions ================================
 //===========================================================================
 
 void PID_autotune(float temp, int extruder, int ncycles)
@@ -342,9 +342,10 @@ void PID_autotune(float temp, int extruder, int ncycles)
     }
     if (cycles > ncycles) {
       SERIAL_PROTOCOLLNPGM(MSG_PID_AUTOTUNE_FINISHED);
-      SERIAL_PROTOCOLPGM("#define  DEFAULT_Kp "); SERIAL_PROTOCOLLN(Kp);
-      SERIAL_PROTOCOLPGM("#define  DEFAULT_Ki "); SERIAL_PROTOCOLLN(Ki);
-      SERIAL_PROTOCOLPGM("#define  DEFAULT_Kd "); SERIAL_PROTOCOLLN(Kd);
+      const char *estring = extruder < 0 ? "bed" : "";
+      SERIAL_PROTOCOLPGM("#define  DEFAULT_"); SERIAL_PROTOCOL(estring); SERIAL_PROTOCOLPGM("Kp "); SERIAL_PROTOCOLLN(Kp);
+      SERIAL_PROTOCOLPGM("#define  DEFAULT_"); SERIAL_PROTOCOL(estring); SERIAL_PROTOCOLPGM("Ki "); SERIAL_PROTOCOLLN(Ki);
+      SERIAL_PROTOCOLPGM("#define  DEFAULT_"); SERIAL_PROTOCOL(estring); SERIAL_PROTOCOLPGM("Kd "); SERIAL_PROTOCOLLN(Kd);
       return;
     }
     lcd_update();