Sounds possibly like the one I just fixed. (though this one went longer than 5 seconds.)

It would do the initial drain pump out, then main wash pump would come on a few seconds, then shut down.

Turns out the main wash pump was worn out, bearings so loose that the rotor jiggled around and caused the motor to draw too much power, which was detected and shut down.

If yours doesn't even do the initial pump out, maybe your machine's drain pump is stuck/jammed/knackered? They work similarly to the wash pump, a three phase pump driven by the computer board, runs about 55 Volts 3 phase if I remember right. If that turns out to be what you need, I have a spare you can have free, just pay postage. I have recently wrecked a Bosch dishwasher about 10 years old - main computer board dead, washpump/heater assembly pinched to fix another machine.  Drain pump salvaged and taking up space... I'm in southern Vic.