Quote Originally Posted by SRR2
There IS no idea behind shorting the battery terminals! There's no basis in fact for doing it. None. Nada. Zip. With a few minor exceptions, all the key switch does is energize a relay that supplies power to the car's systems. Without power to the switch at the key, that relay doesn't energize, so turning the key accomplishes exactly *nothing*.

You will reset everything that needs resetting by simply disconnecting the negative terminal to the battery and leaving it off for a couple minutes. That's enough for any load using battery keep-alive to self-discharge.

If you were smart, you wouldn't disconnect the battery at all, since it's such a nuisance to re-set all the things that 'forget' like clock, OBC values (range, mileage), seats, radio, etc. It's much easier just to pull the connector off the ECU. It's four screws to take the cover off, and then pop the connector off. Couldn't be easier. Give it a minute and reassemble.
I agree with the second a third paragraph, there is nothing to be gained from shorting the connectors. Removing the ECU will reset it, but what about the transmission computer?