Index: dialin/dg/hd_proxy.py
===================================================================
diff -u -r9c3fc0c2986d9b12f6ee850d63bacf4c440081a6 -r8e9a7108959ccde42b6fd731f447f7881759ffb6
--- dialin/dg/hd_proxy.py	(.../hd_proxy.py)	(revision 9c3fc0c2986d9b12f6ee850d63bacf4c440081a6)
+++ dialin/dg/hd_proxy.py	(.../hd_proxy.py)	(revision 8e9a7108959ccde42b6fd731f447f7881759ffb6)
@@ -40,7 +40,7 @@
         self.can_interface = can_interface
         self.logger = logger
 
-    def cmd_switch_reservoirs(self, reservoir_id: int = RESERVOIR1) -> int:
+    def cmd_switch_reservoirs(self, reservoir_id: int = RESERVOIR1,  use_last_trimmer_dc: int = 0) -> int:
         """
         Constructs and sends the switch reservoirs command.
         Constraints:
@@ -56,7 +56,8 @@
         """
 
         res = integer_to_bytearray(reservoir_id)
-        payload = res
+        dc = integer_to_bytearray(use_last_trimmer_dc)
+        payload = res + dc
 
         message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_dg_ch_id,
                                               message_id=MsgIds.MSG_ID_DG_SWITCH_RESERVOIR_CMD.value,