if no one has installed and incorrectly wired in a backup alarm, this is a bad directional switch or the wiring to or from it. I was just mentioning a p22 code in a different thread. P22 is either no signal in any direction or neutral, or a signal in more than 1 position (ie., a signal in both neutral and forward or reverse), from the directional control lever to the {can bus of} vcm/ecm/display panel