how do i test my vss and my tps?

[78fordf150ranger]

My Speedo has never work for as long as I have owned along with the over drive.I found a bunch of burnt wires going to the over drive solinode and vss, I fix the wires and inspected the vss gear for signs of wear and nothing seemed out of place.

What else could it be and how do I test the system?

[directinjktn1stgen]

u really need a wiring diagram of it and check reistance with an ohm meter and voltage where it should be and for good grounds is where id start you should find your problem