diff --git a/ampel-firmware/co2_sensor.cpp b/ampel-firmware/co2_sensor.cpp
index 2cf89e628ccaf32b14153d5cfa9d4bbfe57a5775..07dff010b96d9b9813591d544285ebf4e9409166 100644
--- a/ampel-firmware/co2_sensor.cpp
+++ b/ampel-firmware/co2_sensor.cpp
@@ -102,6 +102,7 @@ namespace sensor {
     Serial.print(getTemperatureOffset());
     Serial.println(F(" K"));
 
+    //FIXME: Actually set auto_calibrate_sensor, depending on the config.
     Serial.print(F("Auto-calibration is "));
     Serial.println(config::auto_calibrate_sensor ? "ON." : "OFF.");