don't let computers or other solid state electronics get wet, and do recognize that the controllers in an electric forklift are 'solid state logic circuits'.
while a good few days air dry may have been able to bring this machine back from getting wet, at this stage I would guess that you are going to bite the bullet and get someone in that can check the SCRs for opens or shorts, the symptom you describe we call a "PMT" (Pulse Monitor Trip), which is caused by a SCR not turning off correctly.