park neutral wire

[gta87305]

I am in the middle of my 5.3 swap in my 95 GMC sierra and the 4 wire plug is need on the 95 for the prndl indicator but the pcm also seems to need it too. I sent my pcm to get vats deleted and all that good stuff and said he programmed it so only one wire is needed on the pcm for park neutral. Is it really necessary to have a park neutral signal to the pcm? I know IAC and im sure a few others rely on it. Can I leave it disconnected or am I gonna have to find where to get the signal from and splice it. I think it is the white wire on the 4 pin harness at the trans switch but unsure. Thanks

[low91]

I may be wrong, but i've made up a few harnesses and never had a wire to the PCM for park/neutral.

[gta87305]

hope so because I dont wanna splice 4 wires into existing wires. I guess I will try it with out and if it doesnt seem right I can always wire it in later. Thanks

[kewljay223]

not trying to hijack, but im kinda in the same boat. i hooked up the complete harness that came with the motor and it runs fine but i dont have the prnd indicator... do i just splice a few of the old wires into the new harness at the 4 pin connecor? which wires are they?

[gta87305]

well I do know that the prndl indicator gets its signal from the 4 pin connector on the trans range switch. At least on a 95 I know it does. Now the 5.3 pcm also uses that connector for I know park neutral at least. So I may try it without connecting it to the pcm and connecting it to the body harness so I have prndl and if the truck does't act right without it I will splice it in afterwards