What is the function of this tool?
When a modern, EFI vehicle isn't running correctly, It can be difficult to diagnose the problem. Whilst you may be able to replicate the fault, sometimes the difference between a failing crankshaft position sensor and a faulty ignitor chip may be very difficult to differentiate. In other instances, the vehicle may be perceived to operate correctly, however an illuminated 'check engine' light on the dashboard may raise concerns. In these instances, a modern engine management computer is designed to record any sensors that are not operational or producing signal within factory specified values. The only difficult part is getting this recorded information off the engine management computer, and into your hands.