[Ground hawg]

There are two buttons just bellow and to the right of the steering wheel.
the one furthest away from steering wheel has front above and rear bellow. this selects the tires to be inflated it has three possitions center possition inflates all tires. the putton nearest the steering wheel opperates the inflate compressor or the deflate valve. press up possition for compressor or down possition for deflate. some times I,ve had problem with the valves being frozzen due to severe cold. this usually fixes it's self after the Hummers been running for a while.

Hope this is of some help

Ground hwg