So I rebuilt my 4r75e got everything back together and it moved A+, took it for a drive then got a trans fault after about a half mile. Took it to a shop got a scan done and revealed a p0731 the tech put it in drive and said it was in 3rd gear, put the truck in 2nd it moved then he put the truck in 1 and it wouldn't move at all it's like the e-brake was on. I know I got the wires in between the motor and trans but only had the bottom bolt tight so I dont think its hurt (not 100% positive).I replaced the tcc,eps solenoid and the dual shift solenoid but not the hard circuit board. I'm confident in the rebuild but having doubts now I'm leaning toward electrical maybe one of A-B solenoid not working any help would be appreciated

 

If you pinched the wires, you must have damaged them.

 

I cant see any visible signs of damage

 

A number of scenarios can lead to a P0731 code being detected and stored. These include:

• Insufficient or contaminated transmission fluid
• A defective shift solenoid
• A mechanical problem or blockage within the transmission
• A defective transmission control module (TCM)
• A shorted or open transmission control circuit

Some of the most common repairs to resolve a P0731 code include:

• Adding more transmission fluid or changing the transmission fluid.
• Replacing a defective shift solenoid.
• Replacing or reprogramming a defective TCM.
• Replacing wiring and/or connectors for a damaged transmission control circuit.

 

How do the wires check electrically? Do they have continuity? Are there shorts to each other, or shorts to ground? If you don't know the answers to these you have NO IDEA if the wiring is good or not. Do the electrical checks, or take it to someone that can do that for you. It's about 99% likely that your problem is in the wiring.

 

Would a connection cause the AB solenoid to lock down in manual low like it's doing.Maybe A side not getting power or vise versa

 

I had precisely these symptoms after rebuilding my 4R75E and I found this post and just one other describing exactly this problem and in neither did the original poster close the loop and solve the mystery.

So here's what causes this problem: If you have the newer intermediate piston return spring and you install it backwards it gets crushed and jams the second clutch. Doh!