diff --git a/tasmota/xsns_15_mhz19.ino b/tasmota/xsns_15_mhz19.ino
index 860eec8ce..633ca3f59 100644
--- a/tasmota/xsns_15_mhz19.ino
+++ b/tasmota/xsns_15_mhz19.ino
@@ -230,7 +230,9 @@ void MhzEverySecond(void)
       mhz_type = (s) ? 1 : 2;
       if (MhzCheckAndApplyFilter(ppm, s)) {
         mhz_retry = MHZ19_RETRY_COUNT;
+#ifdef USE_LIGHT
         LightSetSignal(CO2_LOW, CO2_HIGH, mhz_last_ppm);
+#endif  // USE_LIGHT
 
         if (0 == s || 64 == s) {  // Reading is stable.
           if (mhz_abc_must_apply) {
diff --git a/tasmota/xsns_17_senseair.ino b/tasmota/xsns_17_senseair.ino
index dee516dff..60614b4c7 100644
--- a/tasmota/xsns_17_senseair.ino
+++ b/tasmota/xsns_17_senseair.ino
@@ -84,7 +84,9 @@ void Senseair250ms(void)              // Every 250 mSec
             break;
           case 2:                // 0x03 (3) READ_CO2 - fe 04 02 06 2c af 59
             senseair_co2 = value;
+#ifdef USE_LIGHT
             LightSetSignal(CO2_LOW, CO2_HIGH, senseair_co2);
+#endif  // USE_LIGHT
             break;
           case 3:                // 0x04 (4) READ_TEMPERATURE - S8: fe 84 02 f2 f1 - Illegal Data Address
             senseair_temperature = ConvertTemp((float)value / 100);
diff --git a/tasmota/xsns_38_az7798.ino b/tasmota/xsns_38_az7798.ino
index 18705dce5..b6b1dffbe 100644
--- a/tasmota/xsns_38_az7798.ino
+++ b/tasmota/xsns_38_az7798.ino
@@ -215,7 +215,9 @@ void AzEverySecond(void)
     }
     response_substr[j] = 0;                 // add null terminator
     az_co2 = atoi((char*)response_substr);
+#ifdef USE_LIGHT
     LightSetSignal(CO2_LOW, CO2_HIGH, az_co2);
+#endif  // USE_LIGHT
     i += 3;                                 // advance to second delimiter
     if(az_response[i] != ':') {
       AddLog_P(LOG_LEVEL_DEBUG, PSTR(D_LOG_DEBUG "AZ7798 error second delimiter"));