-08 refers to an accel input to the logics card. the input voltage should be at about 3.5 volts DC at the term board on the card, position 1. so if you are stepping on the Accel pedal, and one of these other connections opens (so the logics card thinks the operator got off the seat or turned off the key switch, [etc...]) you can get this code.
be very careful in the controller area, there can be considerable current stored even when the battery is disconnected.
Just knowing what a code means, without fully understanding the cause and effect can be dangerous. I would STRONGLY suggest you work under the supervision of someone that knows what "static return to off" is...
and get the drive wheels off the ground before you go testing stuff..
my book shows an input to the term board (position 2) that comes from the brake switch and the accel start switch circuit, and says code -04.is related to that circuit.
someone with an EV100 handset could come in and adjust the time delay for the seat switch too, and allow more than micro second open so that hitting a bump does not throw the code so quickly.