Hi boss hoss, I'm afraid I can't help with schematic maybe someone else can help with that request, my experience with this truck tells me to check the dead man sensor the foot brake sensors and the battery interlock sensor. These sensors have an LED light at the cable end of the sensor and show up blue when activated they either go of or come on, check them for adjustment and activation when pedals are operated. If you get wear on the battery interlock securing pin the battery sometimes is not close enough to the sensor to activate. It is usually a sensor problem or adjustment.