Can a faulty anti theft CPU keep my engine from cranking? Checked voltage from the starter switch to the engine cut realay and it's good. No voltage is going out. I've tried swapping out a known good (took it off my working RX-7) and still no voltage out. Looking at the schematic, relay trip voltage comes in from the antenna fuse and that it present. On the other side is a wire that goes out to the Anti theft CPU and it looks like this completes the circuit to trip the relay, but there is neither a ground( expected) or voltage on this wire. When it depress the door locks to engage the alarm, I get a series of rapid beeps and the security light on the console does not flash as it does on my other S5. Where is the CPU? Is it located inside the black box that houses the flasher and horm CPU or is it the silver one located aft of that?

 

There are two Black/Green wires at the Starter Cut Relay. One is thicker in gauge than the other B/G wire. Jumper the thicker B/G wire to the Black/Blue wire and the relay will be effectively bypassed. The outgoing voltage on the thicker B/G wire proceeds on to the Interlock Switch before running to the starter solenoid.

 

I guess the answer is yes. I replaced the Anti Theft CPU and the car started right up.