You have to unlock your meter panel to make changes to the power settings, after it is unlocked it has to be locked. If someone happened to unlock it to make changes I doubt they entered the same button sequence to re-lock it, therefore you should be able to make adjustments to the settings. What setting are you at now M,P,E, or H? H= high power, P= factory setting, E= economy, M=Manual. You can not change the power settings, unless it is unlocked, and you will need access to a service manual for the number sequence to unlock it if it is. Press 1 and 4 and see what it allows you to change.

Break out the operators manual/handbook. I am thinking it will show how to set it.

sounds to me like you need to reset everything and slow down the highest mode speed so the truck cannot go any faster than you want it to , then reset your master password to something he cant figure out. Next time he's caught relentlessly pushing buttons i'd give him some time off for tampering with the equipment. :o/