Where is the lock up solenoid on a axn4 transmission it is not getting a signal and it will not shift in to over drive?

The lockup solenoid does not control OD shift. The lockup solenoid controls torque convertor lockup. Torque converter lockup isn't a gear at all, but a fuel saving function that kicks in when you are cruising, which is a clutch in the torque converter that locks down and overrides the fluid coupling so you dont loose engine engine torque due to the normal fluid coupling of the torque converter. In effect, it overrides the torque converter completely, and provides a direct drive from the engine to the input shaft of the transmission. TC lockup does occur in OD, but it is a separate function. OD is achieved in the AX4N when the OD band holds the front planetary sun gear stationary. This is done by the OD servo and piston assembly, when fluid is directed there through a valve in the valve body. You could have a problem in any of those areas causing you not to have OD.