diff --git a/main.c b/main.c
--- a/main.c
+++ b/main.c
@@ -162,13 +162,15 @@ void update_temp() {
 
     if(temp_pre & 0b0000000000000010) {
         ssd1306_clearscreen();
-        //ssd1306_DrawString("Fatal Error", 3, 35);
-        HAL_Delay(100);
+        HAL_Delay(100); // FIXME: remove?
+        status.tc_errno = 4;
         status.state = STATE_TC_ERROR;
         status.temp = 0;
         status.temp_frac = 0;
     }
     else if(temp_pre & 0b0000000000000001 && !set.ignore_tc_error) {
+        status.tc_errno = 1;
+        HAL_Delay(100); // FIXME: remove?
         status.state_resume = status.state;
         status.state = STATE_TC_ERROR;
         status.temp = 0;