Rigging up a Park/Neutral input in my installation (55 Chevy) is gonna be difficult. Not impossible but I'm wondering....what does that input do in the system? What is the downside of not using it? Can I change the program to negate the bad effects? And lastly where can I learn how this (or any other) input affects the system? I'm trying to understand anht_hac but I dont really have the big picture. Guidance anyone??

Thanks

Steve Huddleston

 

Jegs sales a park/neutral switch for the transmission. I swapped the standard out for an auto in my vette and just used the neutral safety switch that came with the shifter to ground the ecm park/neutral wire. Also, the only thing I noticed without it installed in my vette is it always stayed in cell 4 while driving. My jeep does the same thing with SD TPI. Always runs in cell 4. After I hooked up the switch in the shifter in my vette and the ecm realized when it was in gear it started shifting around into different cells.

 

My twisted mind say to hook the p/n input wire to a toggle,not the shifter if you have major problems mounting.

 

My shifter only has a single N.O. contact for park/neut for the starter safety and the ckt goes to 12v when the starter is engaged. It doesnt look practical to use a switch with two poles cause the room is so tight there. Right now I'm thinking of just getting rid of the starter safety ckt and using the switch for the ecm input. Ill just have to make sure its in park when I start it.

 

It shouldn't be too hard to rig up a relay to drive the ECM. Get a spdt (single pole double throw) 12V relay. If you have 12V when in neutral then use the normally open contact and if you have 0V when in neutral then use the normally closed contact.

 

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