97 Yukon Tranny issue after dash swap

[Rider Jones]

Hi All. I have a 97 GMC Yukon I just acquired. I replaced the dash pad this weekend as old one rotted & broken into 4 separate pieces. The only electronic I swapped was the power steering module. All others & wiring remained the same. Current symptoms are:

- Hard engagement when shifted in gear at park, PND321 all engage/disengage correctly when moving column shifter)

- in drive get very little fwd movement, lack of power(tranny in high gear??)

- reverse seems good/has power, does engage hardas well

I'm now getting the following codes:

P0740 - torque converter/clutch ckt open

P0753 -shift solenoid “A” electrical

P0785 - shift timing solenoid “A"

P1860 - TCC PWM Solenoid Circuit Electrical

I've validated 12v passing through fuses & also have 11.9v at pink wire(E) on tranny plug.

Anyone have ideas or additional testing I should do?

Thank you.

[Rider Jones]

Update....
I pulled dash out, cleared ECM and it ran normally. I inspected wiring & connectors but found no visible problems. I re taped the harness, especially where it splits or Y's when it comes out of firewall. I did notice a tight fit at the Y where harness fits into a metal raceway. I suspect wire(s) were being pulled there or at the ECM plug as it's a tight fit. The bad part is dash pad cracked by windshield...arrrg.

[2018GMC]

Thanks for updating with solution. Time for a dashmat. :-)