AoA. Guys i am asking this from behalf of my brother.

My brother owns a 2007 Toyota Corolla (JDM version but Left Hand Drive and Known as Corolla X ASSISTA here) in KSA. His car is not equipped with RPM meter so he bought an Speedometer with RPM meter from Bilal Gunj. He has installed it but RPM is not working rest all is fine. He lives in outskirt of the city so mechanics have no information regarding wiring. Does anyone know to wire it? I have heard that a wire needs to be hooked with an OBD pin?