[ImperialCrown]

Welcome to Allpar. The 42RE transmission? With the electronic governor and speed sensor not connected to the PCM, it may not know how fast the vehicle is traveling and therefore may stay in first. Does your speedometer work? Any 'ck eng' light or stored 'P' fault codes in the odometer display?
http://www.youtube.com/watch?v=WpisTNiHgkg

 

[wrgarrett]

Welcome to Allpar. The 42RE transmission? With the electronic governor and speed sensor not connected to the PCM, it may not know how fast the vehicle is traveling and therefore may stay in first. Does your speedometer work? Any 'ck eng' light or stored 'P' fault codes in the odometer display?
http://www.youtube.com/watch?v=WpisTNiHgkg

Thanks for the reply. It is returning code 0700. I have a man coming by this afternoon with his new scanner which he says can delve into the PCM and tell exact pin number on PCM that is the problem. Probably have to send PCM off to SIA Electronics to be repaired/reprogrammed.

 

[ImperialCrown]

The PCM/TCM wouldn't be my first suspect. I would more suspect a wiring or transmission sensor issue. Your transmission may be the 42RLE which has more electronics than the older 42RE.
Code P0700 does indicate that a transmission-specific fault code is present.

 

[Bob Lincoln]

How was the original harness damaged - fire, abrasion, pests? The damage may not have been confined to the harness.