The Mini Commander ACC can operate in a special mode for controlling sounds and couplers.  Applications for this feature are targeted for adding a sound system to rolling stock.  Use the Mini Commander ACC when lighting is not directional, such as an interior light in a caboose.  To enable this mode of operation, configure the Mini Commander as an ENG class, then press AUX1 + 0.  This modifies the behavior of the Mini Commander ACC outputs as follows:

• HC1 and HC2 outputs are controlled by the F and R keys respectively

• Voltage and Timing on HC1 and HC2 are set to control coil couplers

• P1 pin 1 is changed from MTRSEL to RailSounds signals

• LC1 and LC2 control and operation are unchanged

The diagram below shows the connections to a Train America Studios sound system. 

CONFIGURATION SUMMARY:
ENG + ## + SET
AUX1 + 0

Note:  For dummy engines, use the Mini Commander Ex, which supports all TR (train) functionality.