99 maxima, remote starter

I am installing remote starter(royal guard ht-800d) on 99 maxima. Car starts fine with remote starter BUT stops immediately as I need to hook up this purple wire to a "wire which changes polarity from negative to positive after starting the car". Wire could be - battery charging indicator wire or oil pressure indicator wire or any other wire with such behavior. I have wiring diagram of maxima but I am having hard time looking for that wire. Where should I look for that wire? Is there any other such wire which is easy to find?

Seems strange, all ign circuits will go from neg to pos on turning the key but BEFORE  not  AFTER starting the car. a fuel pump primer will run pos on start but drop out as soon as engine fires up. I think you might be loking for a tach wire, search remote start '99 Maxima. I used to take it from the rev counter on my Maxies.

The purple wire you spoke of..... is this on the car, or from the remote starter?  Either way, what is it for?