NikP

I have a Lokar shifter which has a normally closed switch when the shifter is in P and N. As I understand it, the PCM needs ground for #32 and #34 so know that transmission is in P or N.

I know I can just connect the PCM wires to one side of the switch and the other to ground and I've accomplished what the PCM needs.

From a wiring standpoint, I also want to make sure the engine can't be started unless it's in P or N.

I assume I need a relay to keep the PCM and starter wiring separate to accomplish this task.

Can all the smart wiring guys validate my thoughts here. I think the picture should do the trick. If not, teach me the flaws in my relay and wiring understanding.

slocaddy

What year nss do you have ? at least 04 and down, the literall starting circut does not pass through the pcm,

NikP

2002 from a GMC Sierra truck.

I realize PCM doesn't need anything from start circuit but from what I read it does need to know if trans is in park or neutral for training on base idle etc...

I know some just leave it out but while I'm here I'd rather give the PCM what it thinks it needs.

I don't have a PRND range switch so that's why I'm trying to incorporate this way and avoid buying one since the PCM only needs to see 32 and 34 grounded in P/N.

ls1nova71

iTrader: (4)

I assume you're going to tune it like an Fbody so you don't need the range sensor, so in that case you only need to ground pin 34, not sure where you came up with needing to do the same with 32? But your schematic shows the PCM only getting that signal during cranking , it should have the signal anytime the ignition is on and the car is in park or neutral, not just when starting it. I will draw you a schematic, but just starting work now, so give me a little time to get it posted.

ls1nova71

iTrader: (4)

This is my thread from several years back on how I wired my wagon. Has been on the road since and works great. https://ls1tech.com/forums/conversio...-question.html

NikP

Brendan @ltswap.com said to send both 32 and 34 to ground so not sure of the full understanding of what's needed in th PCM, but he certainly knows more than me.

Thanks, makes sense now to have 12v power all time to the PCM side relay. I had it covered for the strart cycle, but wasn't thinking about the PCM during just a normal running condition where the trans might be in P / N.

That's the input I needed. Thanks.