1997 Power Take-Off Feed?

[Patrick Feeley]

On the 97 PSDs, there is a Light Blue wire with a Yellow trace (circuit 323) from the PCM that is labeled "Power Take-off Feed" in the EVTM. It goes through the Firewall Feed-Through connector C202, but I can't figure out where it goes (based on the EVTM). Does anyone know what it does (get a signal, give a signal, etc)? Has anyone used it for anything? Just a curiosity thing since the EVTM is basically silent on it except to show it in the connector pin-outs and in the engine controls diagram (just a short line with a title block). The 94-96's don't have it. Cheers!

[BigFuel]

It goes to the transmission range sensor pin 3. From there I do not know.

[BigFuel]

Got it. It is the return line to the PCM that tells it that the TRS is in a selected "gear".

[Patrick Feeley]

Thanks for the response Matt (you are the first in all the forums I'm on to take a stab at it )
That's the same color wire, but a different circuit (323 vice 199) and different PCM pin. Cheers!

[Diesel_brad]

Why is it even there in an auto? To sense a load and slightly raise the idle?

[BigFuel]

Sorry, now I'm really interested as my truck probably also has this wire. I read "PTO" and immediately went to the transmission. What pin on the PCM is it running from?

[Patrick Feeley]

That would be pin 4 on a 1997 Cali PCM. Cheers!

[Patrick Feeley]

After a tad more research, I think I've got the idea. This thread from another 99+ forum sort of explains it, although their topic is different: TheDieselStop.Com Forums: idle control on the cheap

Cheers!