96 blazer 4x4 that has a p1860 code. I have replaced the tcc sensor, and a new harness inside the transmission. I have unplugged the ignition switch and put in a new one and it not help. it acts kind of weird because I can reset the light while I'm driving and it will stay off and shift fine until I stop. Every time I stop it comes back on. I can be rolling in neutral and it will not come back on until it stops. Trying to figure out if this is a problem that a new transmission would fix or if it's some kind of electrical problem elsewhere.

 

I have the same problem!