NEWBIE WITH TRANNY ISSUE

Hey ther. I am new to the jeep world. I just bought my first one.91XJ,4.0L,4x4,automatic AW4 tranny. The tranny is in fail safe mode.It will not downshift to first. I can manually shift it fine though and all other gears seem fine. Could this be a shift solenoid or TPS? Any ideas would be great.Thanks

Might be a solinoid problem. TPS will give other types of problems like the torque converter unlocking at higher speeds and sounds like it is slipping or downshifting to a lower gear from 3rd or OD to the next lower gear.
Hope this helped.
BTW have you changed the tranny fluil recently? The AW4 takes Dexron II or III not the regular ATF.

Got it. It was a solemoid.Replaced them,fluid and filter.Thanks