C28 codes are usually caused from the lift solenoid welding closed causing the R1 precharge resistor to get hot and open. Just replace the the solenoid. If you are in a pinch. You can tap on the solenoid to free it to be able to get it to pass selftest.

313433-000 RESISTOR-PRE CHARGE.... Found it. Thanks for your help stam

Unfortunately the truck has changed in 2015. It is more of a disposable unit than it was.... I don't have a parts book and don't plan on getting one as I have none to service yet. Good luck.

No. Sounds like there has been a change to the control system in 2015 as I have never seen a brake release switch or the component you are speaking of. I will do some digging.

I'm not sure what part it is , but I swapped out what looks like its a relay of some sort. its white , about an inch long by a half inch. Was towards the top left under the brake release switch and had two black wires coming out of it leading to what looks to be a diode glued to the front... I cant find this part in my parts book , but its what made it work when I switched it from another ride ,... any idea what it may be or the part number?

check for voltage at connector J5-16 on the motor controller (wrt B-). check in parallel, report back with findings.

I suspect you have a problem with your harness as you have replaced all components.

Yes , I tried plugging it in to 2 other known good battery packs

Have you tried a known good battery in the unit?
There are many troubleshooting tips logged in the mechanical troubleshooting section here for Raymond 102xm / 102t-f45l, had a look?