Index: dialin/dg/reservoirs.py
===================================================================
diff -u -r812bbf1e5b3b2f1c4f5cfbef1264787e18afb5c3 -r5120ddfc3108ba5b8280adf73c4523c11feb935b
--- dialin/dg/reservoirs.py	(.../reservoirs.py)	(revision 812bbf1e5b3b2f1c4f5cfbef1264787e18afb5c3)
+++ dialin/dg/reservoirs.py	(.../reservoirs.py)	(revision 5120ddfc3108ba5b8280adf73c4523c11feb935b)
@@ -14,11 +14,13 @@
 #
 ############################################################################
 import struct
+from logging import Logger
+
 from ..protocols.CAN import (DenaliMessage,
                              DenaliChannels)
 from ..utils.base import _AbstractSubSystem, _publish
 from ..common.msg_defs import MsgIds, MsgFieldPositions
-from logging import Logger
+from ..utils.conversions import integer_to_bytearray
 
 
 class DGReservoirs(_AbstractSubSystem):
@@ -75,6 +77,28 @@
         """
         return self.drain_to_vol_ml
 
+    def cmd_switch_reservoirs(self, reservoir: int):
+        """
+        Sends a command to the DG to switch reservoirs
+        @param reservoir: (int) the new reservoir number
+        @return: True if command sent, False if invalid reservoir provided
+        """
+
+        if reservoir not in [0, 1]:
+            return False
+
+        payload = integer_to_bytearray(reservoir)
+
+        message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_dg_ch_id,
+                                              message_id=MsgIds.MSG_ID_DG_SWITCH_RESERVOIR_CMD.value,
+                                              payload=payload)
+
+        self.logger.debug("Sending command to switch DG reservoir to {0}".format(reservoir))
+
+        self.can_interface.send(message, 0)
+
+        return True
+
     @_publish([
         "active_reservoir",
         "fill_to_vol_ml",