diff --git a/docs/4_2_co-simulation_api.adoc b/docs/4_2_co-simulation_api.adoc
index 9caefe390..9bf84aeb2 100644
--- a/docs/4_2_co-simulation_api.adoc
+++ b/docs/4_2_co-simulation_api.adoc
@@ -103,7 +103,7 @@ _Both arguments <<currentCommunicationPoint>> and <<communicationStepSize>> allo
 _[The FMU can use this flag to flush a result buffer.]_
 
 * [[eventHandlingNeeded,`eventHandlingNeeded`]] <<eventHandlingNeeded,`eventHandlingNeeded = fmi3True`>> indicates that an event was encountered by the FMU at <<lastSuccessfulTime>> and the importer has to enter <<EventMode>> by calling <<fmi3EnterEventModeCS>>.
-<<eventHandlingNeeded,`eventHandlingNeeded = fmi3True`>> must not be signaled, if the importer indicates to not support <<EventMode>> by <<eventModeUsed,`eventModeUsed = fmi3False`>>.
+<<eventHandlingNeeded,`eventHandlingNeeded = fmi3True`>> must not be signalled, if the importer indicates to not support <<EventMode>> by <<eventModeUsed,`eventModeUsed = fmi3False`>>.
 _[This is different from <<earlyReturn>> which only indicates that the <<fmi3DoStep>> did not complete the intended step up until <<currentCommunicationPoint>> + <<communicationStepSize>> and does not require event handling.]_
 
 * [[terminateSimulationDS,`terminateSimulation`]] When <<terminateSimulationDS,`terminateSimulation = fmi3True`>>, the FMU requests to stop the simulation and the importer must call <<fmi3Terminate>>.
@@ -115,6 +115,10 @@ Reasons for <<earlyReturn, `earlyReturn = fmi3True`>> are
 ** expressed by the return arguments <<eventHandlingNeeded>> or <<terminateSimulationDS>> of <<fmi3DoStep>>, or
 ** the FMU's reaction to the importers request for <<earlyReturn>> by the return argument <<earlyReturnRequested, `earlyReturnRequested = fmi3True`>> of <<fmi3IntermediateUpdateCallback>>, or
 ** the FMU's request for a communication point at <<lastSuccessfulTime>> for any other reason.
++ 
+<<earlyReturn,`earlyReturn = fmi3True`>> must not be used to signal that the requested step was not completed due to an error _[(e.g. integrator encountered division by zero)]_.
+Instead, the function must return with an error code (<<fmi3Error>> or <<fmi3Fatal>>).
+Alternatively, the function can return with <<fmi3Discard>>, if the FMU is in the same state as before the call, i.e. the output argument values are undefined, but the computation may continue.
 
 * [[lastSuccessfulTime,`lastSuccessfulTime`]] `lastSuccessfulTime` represents the internal time latexmath:[t_{i+1}] of the FMU when <<fmi3DoStep>> returns, for any value of <<earlyReturn>>.
 It is possible that the <<lastSuccessfulTime>> is equal to <<currentCommunicationPoint>> when <<earlyReturn,`earlyReturn = fmi3True`>> to indicate, for example, the detection of an event at <<currentCommunicationPoint>>.