diff --git a/homeassistant/components/modbus/climate.py b/homeassistant/components/modbus/climate.py
index 1138734b5bf..b3d6c78387d 100644
--- a/homeassistant/components/modbus/climate.py
+++ b/homeassistant/components/modbus/climate.py
@@ -467,9 +467,6 @@ class ModbusThermostat(BaseStructPlatform, RestoreEntity, ClimateEntity):
 
     async def _async_update(self) -> None:
         """Update Target & Current Temperature."""
-        # remark "now" is a dummy parameter to avoid problems with
-        # async_track_time_interval
-
         self._attr_target_temperature = await self._async_read_register(
             CALL_TYPE_REGISTER_HOLDING,
             self._target_temperature_register[
diff --git a/homeassistant/components/modbus/cover.py b/homeassistant/components/modbus/cover.py
index 5e7b008ff7c..23a09431072 100644
--- a/homeassistant/components/modbus/cover.py
+++ b/homeassistant/components/modbus/cover.py
@@ -123,8 +123,6 @@ class ModbusCover(BasePlatform, CoverEntity, RestoreEntity):
 
     async def _async_update(self) -> None:
         """Update the state of the cover."""
-        # remark "now" is a dummy parameter to avoid problems with
-        # async_track_time_interval
         result = await self._hub.async_pb_call(
             self._slave, self._address, 1, self._input_type
         )
diff --git a/homeassistant/components/modbus/entity.py b/homeassistant/components/modbus/entity.py
index 10ce211fc25..eaf13d5bca4 100644
--- a/homeassistant/components/modbus/entity.py
+++ b/homeassistant/components/modbus/entity.py
@@ -380,8 +380,6 @@ class BaseSwitch(BasePlatform, ToggleEntity, RestoreEntity):
 
     async def _async_update(self) -> None:
         """Update the entity state."""
-        # remark "now" is a dummy parameter to avoid problems with
-        # async_track_time_interval
         if not self._verify_active:
             self._attr_available = True
             return
diff --git a/homeassistant/components/modbus/sensor.py b/homeassistant/components/modbus/sensor.py
index 767fed5fceb..a11e25b4dd4 100644
--- a/homeassistant/components/modbus/sensor.py
+++ b/homeassistant/components/modbus/sensor.py
@@ -106,8 +106,6 @@ class ModbusRegisterSensor(BaseStructPlatform, RestoreSensor, SensorEntity):
 
     async def _async_update(self) -> None:
         """Update the state of the sensor."""
-        # remark "now" is a dummy parameter to avoid problems with
-        # async_track_time_interval
         self._cancel_call = None
         raw_result = await self._hub.async_pb_call(
             self._slave, self._address, self._count, self._input_type