Index: firmware/App/Controllers/Heaters.c
===================================================================
diff -u -r8059b3b67364c3593091a23266f33186430ffe26 -r853d846a60d61d1c6f8987d9cdcfc2bc32913840
--- firmware/App/Controllers/Heaters.c	(.../Heaters.c)	(revision 8059b3b67364c3593091a23266f33186430ffe26)
+++ firmware/App/Controllers/Heaters.c	(.../Heaters.c)	(revision 853d846a60d61d1c6f8987d9cdcfc2bc32913840)
@@ -181,20 +181,34 @@
 
 /*********************************************************************//**
  * @brief
- * The setHeatersTargetTemperature function sets the heaters' target temperature.
+ * The setPrimaryHeaterTargetTemperature function sets the primary heater
+ * target temperature.
  * @details Inputs: none
- * @details Outputs: primaryHeaterTargetTemperature, trimmerHeaterTargetTemperature
- * @param targetTempPtr pointer to target temperature data record
+ * @details Outputs: primaryHeaterTargetTemperature
+ * @param targetTemp target temperature for the primary heater
  * @return none
  *************************************************************************/
-void setHeatersTargetTemperature( TARGET_TEMPS_PAYLOAD_T *targetTempPtr )
+void setPrimaryHeaterTargetTemperature( F32 targetTemp )
 {
-    primaryHeaterTargetTemperature = targetTempPtr->targetPrimaryHeaterTemp;
-    trimmerHeaterTargetTemperature = targetTempPtr->targetTrimmerHeaterTemp;
+    primaryHeaterTargetTemperature = targetTemp;
 }
 
 /*********************************************************************//**
  * @brief
+ * The setTrimmerHeaterTargetTemperature function sets the trimmer heater
+ * target temperature.
+ * @details Inputs: none
+ * @details Outputs: trimmerHeaterTargetTemperature
+ * @param targetTemp target temperature for the trimmer heater
+ * @return none
+ *************************************************************************/
+void setTrimmerHeaterTargetTemperature( F32 targetTemp )
+{
+    trimmerHeaterTargetTemperature = targetTemp;
+}
+
+/*********************************************************************//**
+ * @brief
  * The startPrimaryHeater function starts the primary heaters. It resets
  * the primary heaters state and sets the main primary heater duty cycle.
  * @details Inputs: primaryHeaterTargetTemperature
@@ -218,6 +232,29 @@
 
 /*********************************************************************//**
  * @brief
+ * The startTrimmerHeater function starts the trimmer heater. It resets the
+ * trimmer heater's state and sets the duty cycle of the trimmer heater.
+ * @details Inputs: trimmerHeaterTargetTemperature
+ * @details Outputs: hasStartTrimmerHeaterRequested
+ * @return status
+ *************************************************************************/
+BOOL startTrimmerHeater( void )
+{
+    BOOL status = FALSE;
+
+    if ( ( trimmerHeaterTargetTemperature >= MINIMUM_TARGET_TEMPERATURE ) && ( trimmerHeaterTargetTemperature <= MAXIMUM_TARGET_TEMPERATURE ) )
+    {
+#ifndef DISABLE_HEATERS_AND_TEMPS
+        hasStartTrimmerHeaterRequested = TRUE;
+#endif
+        status = TRUE;
+    }
+
+    return status;
+}
+
+/*********************************************************************//**
+ * @brief
  * The stopPrimaryHeater function stops the primary heater.
  * @details Inputs: none
  * @details Outputs: Primary heater stops
@@ -269,6 +306,7 @@
         {
             cmdResponse.rejected = FALSE;
     #ifndef DISABLE_HEATERS_AND_TEMPS
+            trimmerHeaterTargetTemperature = heaterCmdPtr->targetTemp;
             hasStartTrimmerHeaterRequested = TRUE;
     #endif
         }
Index: firmware/App/Controllers/Heaters.h
===================================================================
diff -u -r8059b3b67364c3593091a23266f33186430ffe26 -r853d846a60d61d1c6f8987d9cdcfc2bc32913840
--- firmware/App/Controllers/Heaters.h	(.../Heaters.h)	(revision 8059b3b67364c3593091a23266f33186430ffe26)
+++ firmware/App/Controllers/Heaters.h	(.../Heaters.h)	(revision 853d846a60d61d1c6f8987d9cdcfc2bc32913840)
@@ -48,9 +48,11 @@
 
 void initHeaters( void );
 
-void setHeatersTargetTemperature( TARGET_TEMPS_PAYLOAD_T *targetTempPtr );
+void setPrimaryHeaterTargetTemperature( F32 targetTemp );
+void setTrimmerHeaterTargetTemperature( F32 targetTemp );
 
 BOOL startPrimaryHeater( void );
+BOOL startTrimmerHeater( void );
 
 void stopPrimaryHeater( void );
 void stopTrimmerHeater( void );
Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -r8059b3b67364c3593091a23266f33186430ffe26 -r853d846a60d61d1c6f8987d9cdcfc2bc32913840
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 8059b3b67364c3593091a23266f33186430ffe26)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 853d846a60d61d1c6f8987d9cdcfc2bc32913840)
@@ -790,7 +790,8 @@
 
         result = TRUE;
         memcpy( &payload, message->payload, sizeof( TARGET_TEMPS_PAYLOAD_T ) );
-        setHeatersTargetTemperature( &payload );
+        setPrimaryHeaterTargetTemperature( payload.targetPrimaryHeaterTemp );
+        setTrimmerHeaterTargetTemperature( payload.targetTrimmerHeaterTemp );
     }
     sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_DG_2_HD, result );
 }