Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -raa8b9687b9396b4878cf0d5327d72a5d67477761 -r57fe78d545ac91ba3f8d38ff76079a0d7ec8c0db
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision aa8b9687b9396b4878cf0d5327d72a5d67477761)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 57fe78d545ac91ba3f8d38ff76079a0d7ec8c0db)
@@ -227,13 +227,19 @@
 {
     BOOL result;
     MESSAGE_T msg;
+    ACK_RESPONSE_PAYLOAD_T cmd;
 
+    // Populate data structure
+    cmd.acknowledgement = ack;
+
     // Create a message record
     blankMessage( &msg );
     msg.hdr.msgID = msgID;
-    msg.hdr.payloadLen = sizeof( U08 );
-    msg.payload[ 0 ] = (U08)ack;
+    msg.hdr.payloadLen = sizeof( ACK_RESPONSE_PAYLOAD_T );
 
+    //Populate message
+    memcpy( msg->payload, &cmd, sizeof( ACK_RESPONSE_PAYLOAD_T ) );
+
     // Serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
     result = serializeMessage( msg, buffer, ACK_NOT_REQUIRED );
 
@@ -255,17 +261,21 @@
 {
     BOOL result;
     MESSAGE_T msg;
-    U08 *payloadPtr = msg.payload;
+    UI_RESPONSE_PAYLOAD_T cmd;
 
+    // Populate data structure
+    cmd.accepted = accepted
+    cmd.rejection_reason = reason;
+
     // Create a message record
     blankMessage( &msg );
     msg.hdr.msgID = msgID;
-    msg.hdr.payloadLen = sizeof( BOOL ) + sizeof( U32 );
+    msg.hdr.payloadLen = sizeof( UI_RESPONSE_PAYLOAD_T );
 
-    memcpy( payloadPtr, &accepted, sizeof( BOOL ) );
-    payloadPtr += sizeof( BOOL );
-    memcpy( payloadPtr, &reason, sizeof( U32 ) );
+    // Populate message
+    memcpy( msg->payload, &cmd, sizeof( UI_RESPONSE_PAYLOAD_T ) );
 
+
     // Serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
     result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );