Have an issue with wiring, using a B&M shifter with microswitches for back up and
neutral feedback for the ECM. The connector at the tail of the auto tx has a looped orange/blk wire and a blue/white and a purple , both were taped off.
My ECM diagram shows an orange/white and a blk/white to give the ECM a signal of gear selection. Its a conversion engine and tx , who ever did the install didn't bother with the wiring for gear selection ( or back up lights).
Any one seen this issue ?

 

https://www.thirdgen.org/forums/tran...ter-relay.html
Have you looked at these schematics the above shows the wiring using a spdt relay.
http://www.austinthirdgen.org/?pid=19
This should be in the electrical section of the forum.

 

Thanks for the quick reply, my main goal is to find the correct color wires that give the ECM a signal telling it the vehicle is in park or neutral. I don't find the expected colors at the transmission. The orange / blk is looped back into the connector . maybe its set up to ground the input to the ecm so it thinks the car is in park/neutral all the time. Its messing up my idle , even though I followed the procedure to get the idle set > jumper the ecm com connector , disconnect the IAC and adjust the screw on the throttle body to 550 rpm in drive, turn off the engine, disconnect power to the ecm and hope for the best. This doesn't work for me, only thing i can think of is the lack of signal from the switch that tells the ecm what gear your in

 

Not sure what you mean bye looped. The wire is direct from the ecm to the p/n switch then to ground to tell the ecm to do a rpm adder. B10 86-89 165 ecm , d16 of the ecm 90-92 730 ecm . The adder isn’t much only 50rpm or so but it can prevent stalling during the engine load transition.

 

Are you using a universal shifter with the 2 separate microswitches, or one made for a 3rd gen f-body? Our cars use an all inclusive switch module bolted to the side of the shifter.

 

Thanks Noemisions & Tuned Performance.
My vehicle is using a B&M Shifter , with 2 microswitches, one for p/n and one for backup lights. The connector that I mention has 1 purple, one blu/white and an orange/blk that is a loop into the pins of the connector. I cant see the colors of the connector this one mates two. Possible the loop jumpers the or/blk to the blk/white ?? This appears to be a factory plug, the purple and blu/white don't connect to anything. I'm looking for a wiring diagram specifically covering the connections to the auto tranny, no luck yet.
I have ECM schematics and lighting/A/C digs., but nothing showing the wiring harness elsewhere.
I might mention this engine/tranny came from a 91 Camaro , appears the wiring harness is factory , not an aftermarket like "Painless".

 

Uhhh... The wiring to the transmission would be for torque converter lockup, or VSS. The switch on the shifter controls neutral safety, reverse lights, and the drive signal to the ECM.

 

What does loop mean ? Connect ??