We have installed the Orion T-Smart DC-DC charger (isolated) with Remote Key on-off. (Diagram (a) in Ch. 4.4 in the manual). The values are Alternator=Regular, Engine Shutdown Start Voltage/Shutdown are respectively: 14V/13.5V. The values for Lockout Voltage/Restart are respectively: 13.0V/13.3V. When ignition starts, Bulk or Absorption charge starts after the input voltage reaches 14V. When the ignition is turned off, it continues charging until the input voltage drops to 13.0V, (Output is still 14.2V) when Charging is turned OFF ("disabled due to Input voltage lock-out"). Almost immediately after that, the message shown is "disabled due to Input voltage lockout, Engine shutdown detected". Why is the Engine shutdown not recognized at 13.5V as indicated in the Shutdown values? (The Shutdown switch is enabled). Thanks!