ok we put 4,0 out of 2001 4x4 explorer into 2000 ranger wich had 3.0 2x4 used 4.0 wiring harness n trans no power to brake light headlight running lights cant put into overdrive wont start with key . but will start with hot wire to starter drive fine but no overdrive. any help or answers GREATLY appreciated

 

I assume you used the 2001 4.0l explorer computer, and are using its PATS key.

2000 Ranger 3.0l and 2001 explorer should have both had Type B PATS, so no starter interrupt, and if engine starts then PATS wouldn't be the issue.
But look in the engine fuse box for a starter relay, PATS module Grounds that relay to allow starting, but it should be grounded all the time with Type B

Automatics use an NSS(neutral safety switch) on the transmission, when you turn the key to START the 12volts runs to NSS and then to starter motors "S" terminal to activate starter motor.
NSS only passes that 12volts if trans is in Park or Neutral, if there is a starter relay then that 12volts activates the relay only, if it is grounded, and relay closing passes a different 12volts to the starter motors "S" post

Reverse lights are also on the NSS.

I don't have a 2000 Ranger wiring diagram but here is a 1999, should be the same, fuse numbers can be different, but wire colors are usually the same.

 

thanks ill check for relay