Read the instructions for the engines. The lock out procedure is the same. So the locosound may just be locked in forward. For PS-2 engine you apply power and let it start up. Turn power off. Does the engine play shutdown sounds for 5-8 seconds and complete a shut down sequence? If not the battery is weak or dead.
Test with smoke off. Getting to reverse is harder to do than forward. Besides powering the processor, the battery has to power the relay for reverse. Sometimes with weak battery that pushes it over the limit and it recycles the board. G