1234 marked the router indicator Department!

1234 marked the router light, is inserted in the first hole is marked with a bright light will be? And so on? I play is the routing of the first hole, but the second light, S 1 of the light does not shine What is the problem!

1 light is not
2 routers lighting circuit board welding problems on the line can be
3 He does not light a pipe liang