diff --git a/src/ara/diag/dtc_information.cpp b/src/ara/diag/dtc_information.cpp
index c35ae5fff..719bd2cc4 100644
--- a/src/ara/diag/dtc_information.cpp
+++ b/src/ara/diag/dtc_information.cpp
@@ -1,21 +1,33 @@
 #include "./dtc_information.h"
+#include "./diag_error_domain.h"
 
 namespace ara
 {
     namespace diag
     {
-        DTCInformation::DTCInformation(const ara::core::InstanceSpecifier &specifier) : mSpecifier{specifier},
-                                                                                        mControlDtcStatus{ControlDtcStatusType::kDTCSettingOff}
+        DTCInformation::DTCInformation(const core::InstanceSpecifier &specifier) : mSpecifier{specifier},
+                                                                                   mControlDtcStatus{ControlDtcStatusType::kDTCSettingOff}
         {
         }
 
-        ara::core::Result<UdsDtcStatusByteType> DTCInformation::GetCurrentStatus(uint32_t dtc)
+        core::Result<UdsDtcStatusByteType> DTCInformation::GetCurrentStatus(uint32_t dtc)
         {
-            /// @todo In case of out_of_range exception return kNoSuchDtc (108) error code
-            UdsDtcStatusByteType _status{mStatuses.at(dtc)};
-            ara::core::Result<UdsDtcStatusByteType> _result{_status};
+            try
+            {
+                UdsDtcStatusByteType _status{mStatuses.at(dtc)};
+                core::Result<UdsDtcStatusByteType> _result{_status};
 
-            return _result;
+                return _result;
+            }
+            catch (std::out_of_range)
+            {
+                core::ErrorDomain *_errorDomain{DiagErrorDomain::GetDiagDomain()};
+                auto _diagErrorDomain{static_cast<DiagErrorDomain *>(_errorDomain)};
+                core::ErrorCode _errorCode{_diagErrorDomain->MakeErrorCode(DiagErrc::kNoSuchDTC)};
+                auto _result{core::Result<UdsDtcStatusByteType>::FromError(_errorCode)};
+
+                return _result;
+            }
         }
 
         void DTCInformation::SetCurrentStatus(
@@ -65,37 +77,37 @@ namespace ara
             }
         }
 
-        ara::core::Result<void> DTCInformation::SetDTCStatusChangedNotifier(
+        core::Result<void> DTCInformation::SetDTCStatusChangedNotifier(
             std::function<void(uint32_t, UdsDtcStatusByteType, UdsDtcStatusByteType)> notifier)
         {
             // In contrast with the ARA standard, no evaluation is perfomed to validate the notifier pointer.
             mDtcStatusChangedNotifier = notifier;
-            ara::core::Result<void> _result;
+            core::Result<void> _result;
 
             return _result;
         }
 
-        ara::core::Result<uint32_t> DTCInformation::GetNumberOfStoredEntries()
+        core::Result<uint32_t> DTCInformation::GetNumberOfStoredEntries()
         {
             auto _size{static_cast<uint32_t>(mStatuses.size())};
-            ara::core::Result<uint32_t> _result{_size};
+            core::Result<uint32_t> _result{_size};
 
             return _result;
         }
 
-        ara::core::Result<void> DTCInformation::SetNumberOfStoredEntriesNotifier(
+        core::Result<void> DTCInformation::SetNumberOfStoredEntriesNotifier(
             std::function<void(uint32_t)> notifier)
         {
             // In contrast with the ARA standard, no evaluation is perfomed to validate the notifier pointer.
             mNumberOfStoredEntriesNotifier = notifier;
-            ara::core::Result<void> _result;
+            core::Result<void> _result;
 
             return _result;
         }
 
-        ara::core::Result<void> DTCInformation::Clear(uint32_t dtc)
+        core::Result<void> DTCInformation::Clear(uint32_t dtc)
         {
-            ara::core::Result<void> _result;
+
             auto _iterator{mStatuses.find(dtc)};
 
             if (_iterator != mStatuses.end())
@@ -105,34 +117,40 @@ namespace ara
                 {
                     mNumberOfStoredEntriesNotifier(mStatuses.size());
                 }
+
+                core::Result<void> _result;
+                return _result;
             }
             else
             {
-                /// @todo Return kWrong error code
-            }
+                core::ErrorDomain *_errorDomain{DiagErrorDomain::GetDiagDomain()};
+                auto _diagErrorDomain{static_cast<DiagErrorDomain *>(_errorDomain)};
+                core::ErrorCode _errorCode{_diagErrorDomain->MakeErrorCode(DiagErrc::kWrongDtc)};
+                auto _result{core::Result<void>::FromError(_errorCode)};
 
-            return _result;
+                return _result;
+            }
         }
 
-        ara::core::Result<ControlDtcStatusType> DTCInformation::GetControlDTCStatus()
+        core::Result<ControlDtcStatusType> DTCInformation::GetControlDTCStatus()
         {
-            ara::core::Result<ControlDtcStatusType> _result{mControlDtcStatus};
+            core::Result<ControlDtcStatusType> _result{mControlDtcStatus};
             return _result;
         }
 
-        ara::core::Result<void> DTCInformation::SetControlDtcStatusNotifier(
+        core::Result<void> DTCInformation::SetControlDtcStatusNotifier(
             std::function<void(ControlDtcStatusType)> notifier)
         {
             // In contrast with the ARA standard, no evaluation is perfomed to validate the notifier pointer.
             mControlDtcStatusNotifier = notifier;
-            ara::core::Result<void> _result;
+            core::Result<void> _result;
 
             return _result;
         }
 
-        ara::core::Result<void> DTCInformation::EnableControlDtc()
+        core::Result<void> DTCInformation::EnableControlDtc()
         {
-            ara::core::Result<void> _result;
+            core::Result<void> _result;
 
             if (mControlDtcStatus != ControlDtcStatusType::kDTCSettingOn)
             {
diff --git a/src/ara/diag/dtc_information.h b/src/ara/diag/dtc_information.h
index c98ea881e..77ed160c5 100644
--- a/src/ara/diag/dtc_information.h
+++ b/src/ara/diag/dtc_information.h
@@ -44,7 +44,7 @@ namespace ara
         class DTCInformation
         {
         private:
-            const ara::core::InstanceSpecifier &mSpecifier;
+            const core::InstanceSpecifier &mSpecifier;
             std::map<uint32_t, UdsDtcStatusByteType> mStatuses;
             std::function<void(uint32_t, UdsDtcStatusByteType, UdsDtcStatusByteType)> mDtcStatusChangedNotifier;
             std::function<void(uint32_t)> mNumberOfStoredEntriesNotifier;
@@ -54,14 +54,14 @@ namespace ara
         public:
             /// @brief Constructor
             /// @param specifier Instance specifier that owns the DTC information
-            explicit DTCInformation(const ara::core::InstanceSpecifier &specifier);
+            explicit DTCInformation(const core::InstanceSpecifier &specifier);
 
             ~DTCInformation() noexcept = default;
 
             /// @brief Get UDS DTC status byte of a certain DTC
             /// @param dtc DTC ID of interest
             /// @returns Requested USD DTC status byte if the DTC ID exists, otherwise an error
-            ara::core::Result<UdsDtcStatusByteType> GetCurrentStatus(uint32_t dtc);
+            core::Result<UdsDtcStatusByteType> GetCurrentStatus(uint32_t dtc);
 
             /// @brief Set UDS DTC status byte of a certain DTC
             /// @param dtc DTC ID of interest
@@ -74,37 +74,37 @@ namespace ara
             /// @brief Set a notifer on any DTC status change
             /// @param notifier Callback to be invoked if the status of any DTC is changed
             /// @returns Error in case of invalid callback pointer
-            ara::core::Result<void> SetDTCStatusChangedNotifier(
+            core::Result<void> SetDTCStatusChangedNotifier(
                 std::function<void(uint32_t, UdsDtcStatusByteType, UdsDtcStatusByteType)> notifier);
 
             /// @brief Get the number of stored DTC
             /// @returns Number of currently stored DTC in the primary fault memory
-            ara::core::Result<uint32_t> GetNumberOfStoredEntries();
+            core::Result<uint32_t> GetNumberOfStoredEntries();
 
             /// @brief Set a notifer on the number of stored DTC change
             /// @param notifier Callback to be invoked if the number of stored DTC is changed
             /// @returns Error in case of invalid callback pointer
-            ara::core::Result<void> SetNumberOfStoredEntriesNotifier(
+            core::Result<void> SetNumberOfStoredEntriesNotifier(
                 std::function<void(uint32_t)> notifier);
 
             /// @brief Clear a DTC
             /// @param dtc ID of the DTC that should be removed
             /// @returns Error if the requested DTC ID does not exist
-            ara::core::Result<void> Clear(uint32_t dtc);
+            core::Result<void> Clear(uint32_t dtc);
 
             /// @brief Indicate whether the UDS DTC byte update is enabled or not
             /// @returns Control UDS status relates to the UDS service 0x85
-            ara::core::Result<ControlDtcStatusType> GetControlDTCStatus();
+            core::Result<ControlDtcStatusType> GetControlDTCStatus();
 
             /// @brief Set a notifer on the control DTC status change
             /// @param notifier Callback to be invoked if the control DTC status is changed
             /// @returns Error in case of invalid callback pointer
-            ara::core::Result<void> SetControlDtcStatusNotifier(
+            core::Result<void> SetControlDtcStatusNotifier(
                 std::function<void(ControlDtcStatusType)> notifier);
 
             /// @brief Enforce enabling the USD DTC status byte update
             /// @returns No error
-            ara::core::Result<void> EnableControlDtc();
+            core::Result<void> EnableControlDtc();
         };
     }
 }
diff --git a/src/ara/diag/ecu_reset_request.cpp b/src/ara/diag/ecu_reset_request.cpp
index ee229d6d9..f62ca92ea 100644
--- a/src/ara/diag/ecu_reset_request.cpp
+++ b/src/ara/diag/ecu_reset_request.cpp
@@ -167,7 +167,7 @@ namespace ara
         {
             if (mResetTypeFuture.valid())
             {
-                /// @todo Reset the ECU based on the requested reset type
+                throw std::logic_error("ECU reset is not supported.");
             }
             else
             {
diff --git a/src/ara/diag/security_access.cpp b/src/ara/diag/security_access.cpp
index 2c9763974..c6311424d 100644
--- a/src/ara/diag/security_access.cpp
+++ b/src/ara/diag/security_access.cpp
@@ -59,7 +59,6 @@ namespace ara
             MetaInfo &metaInfo,
             CancellationHandler &&cancellationHandler)
         {
-            /// @todo Consider the cancellation handler
             uint8_t _nrc;
             OperationOutput _response;
             std::promise<OperationOutput> _resultPromise;
@@ -99,6 +98,10 @@ namespace ara
                         _suppressPositiveResponse);
                 }
             }
+            else if (cancellationHandler.IsCanceled())
+            {
+                GenerateNegativeResponse(_response, cGeneralReject);
+            }
             else
             {
                 GenerateNegativeResponse(_response, _nrc);
diff --git a/src/ara/diag/security_access.h b/src/ara/diag/security_access.h
index c0343d9e6..556262342 100644
--- a/src/ara/diag/security_access.h
+++ b/src/ara/diag/security_access.h
@@ -46,6 +46,7 @@ namespace ara
             const size_t cKeyLength{2};
 
             const uint8_t cSuppressPosRspMask{0x80};
+            const uint8_t cGeneralReject{0x10};
             const uint8_t cInvalidKey{0x35};
             const uint8_t cExceededNumberOfAttempts{0x36};
 
diff --git a/src/ara/exec/deterministic_client.cpp b/src/ara/exec/deterministic_client.cpp
index 0d3887da5..0980c7588 100644
--- a/src/ara/exec/deterministic_client.cpp
+++ b/src/ara/exec/deterministic_client.cpp
@@ -57,9 +57,8 @@ namespace ara
         {
             std::unique_lock<std::mutex> _lock(mCycleMutex);
             mCycleConditionVariable.wait(_lock);
-
-            /// @todo Return proper value based on the client current lifecycle
             core::Result<ActivationReturnType> _result{ActivationReturnType::kRun};
+            
             return _result;
         }
 
diff --git a/src/ara/exec/state_client.cpp b/src/ara/exec/state_client.cpp
index fea5cc448..04df85ffc 100644
--- a/src/ara/exec/state_client.cpp
+++ b/src/ara/exec/state_client.cpp
@@ -156,7 +156,6 @@ namespace ara
         core::Result<ExecutionErrorEvent> StateClient::GetExecutionError(
             const FunctionGroup &functionGroup) noexcept
         {
-            /// @todo Implement set state tracking
             const ExecErrc cExecErrc{ExecErrc::kFailed};
             auto _errorValue{static_cast<core::ErrorDomain::CodeType>(cExecErrc)};
             core::ErrorCode _errorCode{_errorValue, cErrorDomain};
diff --git a/test/ara/diag/ecu_reset_request_test.cpp b/test/ara/diag/ecu_reset_request_test.cpp
index e5c119419..31b1f3ce6 100644
--- a/test/ara/diag/ecu_reset_request_test.cpp
+++ b/test/ara/diag/ecu_reset_request_test.cpp
@@ -129,8 +129,6 @@ namespace ara
                     GeneralMetaInfo,
                     std::move(_cancellationHander))};
             EXPECT_TRUE(_succeedFuture.valid());
-
-            EXPECT_NO_THROW(Service.ExecuteReset(GeneralMetaInfo));
         }
 
         TEST_F(EcuResetRequestTest, EnableRapidShutdownMethod)