Sounds like a short with that wire, I would follow it and see where it leads, or your interlock switch failed (black and red wire), or antitheft system failed or engaged it self (black and green wire). I am looking at an 86 RX7 diagram as well if it is a different year please post and I will get you the correct wire colors.

the car is an 86 i have bypassed the interlock switch and i have no anti theft system it is bypassed also

Did you check the circuit breaker relay?

theyy were fine didnt need reset

Whats your volts when the switch is in the run position?

0 switch only has volts on the off position

where are you taking the reading at?

im am testin volts on the w/r wire on the back of the ignition switch its got 12v in the off position but is says .50v on acc and 0 on start

just for giggles meter at the battery and see what happens. If the volts drop way off you may have a short.

I still assert that you have a bad connection at either the battery or a ground. Check your voltage there when you try to start and at the main relay in the engine bay. I believe it's labeled XM-1 in the wiring diagram.

I thought I have metered my car at the switch before and have similar results but the car started. post a pic of where you are metering if you can.

The only thing it can be at this point is crossed wire, failed relay(s), or a bad connection(s), or short(s).

ok so ive been tracing wires checking connections and grounds all are clean, i opend up the ignition switch that was told was working condition and it was rusted to hell so i orderd a brand new switch from mazda, how is it possible that all 4 ignition switches are bad and showing the same volts in the acc position and run position .

perhaps a design fault?

you could jump wires and see if that works