30
Fig 4-9
This function allows the device to send information to and receive
information from, vehicle control modules. For example, in the case of
OBD II generic information Mode 1 (which relates to data parameters),
the scan tool user initiates a request for information from the
powertrain control module (PCM), and the PCM responds by sending
the information back to the scan tool for display. Most enhanced scan
tools also can actuate relays, injectors, and coils, perform system
tests, etc. Users could check the individual part to see what is working
properly by actuation test.