The technician will try to start the vehicle and observe what happens. There may be no sound, a clicking sound, or the car may sound like it's cranking normally but just failing to catch. The dash lights should dim when the key is turned, and the fuel pump should be heard at some point before the key is turned to start the engine.
In most cases, no-start problems are caused by the starting and charging system. The technician can test this system using a diagnostics machine. If the starting system functions properly, the technician will use a different scanner to read
OBD trouble codes, and will test other components or read sensor inputs.