A newbie to the forum, perhaps someone can help me!

I have a GEM/CASE IH 2600TS trailed sprayer with an 844 model controller (built in 2000) where the cable between the 844 controller and the sensors/pressure control has been damaged, patched and repaired in the past and now needs to be replaced. Does anyone have, or indeed know where I can get, a wiring diagram for this sprayer, or even details of the 844 controller 28 pin connector? Neither the 2200TS-3600TS Operators Manual (Don 6-22990) nor the 844 Operators Manual (Don 6-23140) which I have include any wiring details/diagrams.