docs: update module reference metadata

docs/en/modules/modules_system.md

@@ -343,7 +343,7 @@ Source: [modules/internal_combustion_engine_control](https://github.com/PX4/PX4-
 
 
 ### Description
-		
+
 The module controls internal combustion engine (ICE) features including:
 ignition (on/off), throttle and choke level, starter engine delay, and user request.
 
@@ -377,18 +377,21 @@ The ICE is implemented with a (4) state machine:
 ![Architecture](../../assets/hardware/ice/ice_control_state_machine.png)
 
 The state machine:
-		
+
 - Checks if [Rpm.msg](../msg_docs/Rpm.md) is updated to know if the engine is running
 - Allows for user inputs from:
-  - AUX{N}
+  - Manual control AUX
   - Arming state in [VehicleStatus.msg](../msg_docs/VehicleStatus.md)
+- In the state "Stopped" the throttle is set to NAN, which by definition will set the
+  throttle output to the disarmed value configured for the specific output.
+
 
 The module publishes [InternalCombustionEngineControl.msg](../msg_docs/InternalCombustionEngineControl.md).
-		
+
 The architecture is as shown below:
 
 ![Architecture](../../assets/hardware/ice/ice_control_diagram.png)
-		
+
 <a id="internal_combustion_engine_control_usage"></a>
 
 ### Usage {#internal_combustion_engine_control_usage}