What does 'ATP'mean on the DASHBOARD OF THE Nissan XE 2002 vehicles?

No, the ATP light comes on when the transfer case is in Neutral and the transmission is in Park. It's there to alert the driver that putting the transmission in Park will not prevent the vehicle from rolling since the axles are disconnected from the transmission's park pawl.

If the transfer case is not actually in Neutral, then it's just a sensor glitch.

This light indicates that the automatic transmission parking function is not engaged. If the transfer control lever is not secured in any drive position while the automatic transmission selector lever is in the P (Park) position, the transmission will disengage and the vehicle may move unexpectedly. Shift the transfer control lever into the 2H, 4H, or 4L position when the warning light comes on.