Comment by ErroneousBosh
7 hours ago
Same. Want to update the firmware in the computer? Sure but you'll need to unscrew the driver's seat, unscrew the desktop PC sized ECU, unscrew its four pencil-thick battery connections, unplug its 27 connectors, unscrew the 50 screws in three slightly different sizes holding the top cover on, remove the heatsinks, unscrew the eight screws holding the motherboard in, and desolder both the 144-pin 68HCxxx chips that do all the thinking.
Refitting is the reverse of removal.
Yes, I have actually already done this.
Surely there's a parallel EPROM somewhere in there you can bake with a UV light and program.
The 68HCxxx's typically have on chip ROMs.