The dash warning lights won't go off on my car because my alternator is not connected to my ecu. I'm not sure how to wire it since I have a S5 alternator on a S4 engine in an 88 convertible. I have the (+) wire of the alternator hooked to the main relay at a wire switched with the ignition, but I don't know where to hook up the second wire that is supposed to go to the ecu. I tried using the write-up on the Rotary ressurection webpage, but it's not that clear and I don't want to fry anything. Could someone tell me which pin on the ecu it goes to.

 

The wires don't go to the ECU. One wire goes to the CPU. It's the White wire with a Black stripe. Not to be confused with the Black wire with a white stripe.

The White/Black wire goes to the CPU. It supplies a Ground for a relay which in turn, turns the idiot lights off. Try it. Put the white/black to ground and see if the lights go out. Idiot lights that is.

I figure you know where the B wire goes.

 

What white and black wire are you talking about? Before converting to a turbo engine, the alternator wires were part of the EFI harness. On the turbo engine the alternator plug comes from the engine harness that comes out the drivers side of the car. Since I'm still using the n/a drivers side engine harness I had to run my own wires for the alternator. I ran one to a switched power source so that the S5 alternator wouldn't drain my battery, but I don't know which wire on the CPU I should connect the other wire( should be W/B) to.
If someone knows the pin position on the CPU to connect it to it would be helpful.

 

Alright, I just looked at the wiring diagram in the FSM. When you said W/B wire, did you mean the one at the CPU plug? So should I cut the W/B wire at the CPU plug and ground it, or should I connect it to the wire on my alternator?

 

The alternator on the series four has a two wire plug on the back of it. One is b/w and the other w/b. One goes to the relay in the CPU that determines if the idiot lights light up or not.

The w/b goes to the CPU. The b/w goes to switched 12v power when the key is to ON or better.

I have a series five alt on a couple of cars. I'll look tomorrow and see where the w/b and b/w are connected on the series five alt.

 

Try this link and just read what Icemark has written on the first page. He explained it pretty good and has pictures. https://www.rx7club.com/showthread.p...ght=ALTERNATOR