Power and output lights indicate test activationincludes wiring harness adapter and instructions it enables you to check cylinder balance by firing individual injectors fires individual injectors in 1/2-second increments in three different ranges: 1 pulse of 500 milliseconds; 50 pulses of 10 milliseconds; 100 pulses of 5 milliseconds three different ranges 1 pulse of 500 milliseconds 50 pulses of 10 milliseconds and 100 pulses of 5 milliseconds performs a cylinder balance test when injectors are suspect in engine performance problems. this vehicle powered tool fires individual injectors in 1/2 second increments in three different ranges: 1 pulse of 500 milliseconds; 50 pulses of 10 milliseconds; 100 pulses of 5 milliseconds. power & output lights indicate test activation. includes wiring harness adapter & instructions.