code reader

I have a Mahindra 2555 tractor that the MIL light came on does anyone know of an inexpensive OBD reader that will read codes on this tractor? I have two both neither will reader the codes on this tractor. Thanks

I am looking for my diagnostics plug on my XG3037. I have read that it is under a shroud on the lower right side of the steering wheel. This is the only plug I can find. It is an 8 pin but only has 7 wires running to it. Is this it and were can I find an adapter to connect an OBD reader?