1. Make sure the OBD-II module you're using is one stated to work on the website, others may be tested and added later but are not likely to work
  2. Make sure the blue power on light on the OBD-II module is on (sometimes it blinks, that's OK)
  3. Make sure the shift light is powering on, there will be a startup sequence where all of the lights come on in sequence and then will turn off. At this point the shift light is waiting for action.
  4. Connect to the shift light with the smart phone app, the shift light should flash a white color and the app will say DISCONNECT at the top over the RPM chart
  5. There should be an orange "OBD2" indication on the top right area of this main screen if the OBD-II module is connected to the shift light
    1. If not, make sure nothing is connected to the green tach signal wire, and the wire isn't bumping against anything (if the shift light receives a tach signal, it will not connect to OBD-II to avoid random connections to other nearby cars)
    2. If that doesn't help, try grounding the green tach wire
    3. If still no help, contact us for support
  6. If there is an orange "OBD2" indicator, but no RPM response, a good way to verify the OBD-II module is actually working is to install one of the free apps that will show real-time data from the module. Usually, the store listing for the OBD-II module will suggest a number of apps.
    1. If the app works and the shift light doesn't, contact us
    2. If the app does not work, either the OBD-II module is malfunctioning or it is not compatible with your vehicle. Despite OBD-II being a standard starting in 1996, some earlier vehicles don't seem to work with these modules. Some sources suggest that after 2006 there is very wide compatibility but before that there are certain vehicles that don't work. Unfortunately, there is not much documentation about this, but users with vehicles like a 1996 Dodge Viper were unable to get the OBD-II module to read RPM.
  7. If none of the above seems to work, you might need to use a tach signal instead. We would be interested to know if this is the case for your vehicle so we can understand what vehicles are not compatible and possibly test other modules in the future to enable more compatibility, please contact us.