These shuttles are diesel engines with 24 volt electrical systems (lots of accessories to run) supposedly the engine computer was fried when someone hooked up the battery to a 12 volt car battery). Is this even possible? How could you ruin an electrical system by plugging in something of LOWER voltage?

my truck had trouble starting, and tried everything to fix it so i finaly took it too a mechanic and he found out that the engine comuter wasent allowing gas in, so he bypassed it and now it runs but should i leave it that way or should i buy a used computer for my truck? and what will happen if i leave it as it is?will it affect my truck?

I'm having electrical problems with my truck, It won't run. Can anyone help me with all the wires on the engine computer? I need a diagram of all the wires and how many amps each wire sends out? That way I can run some tests. HELP!?!

trying to design an engine using computer software. Any recommendations/suggestions? How do I go about it?