trans. not shifting

[roboto1720]

My problem is the auto trans will not up or down shift most of the time. I noticed that if the overdrive light will not turn on and off the trans will not shift.Sometimes it will work but most of the time it won't. I can turn the ign switch on and off a few times and it may work. If it's not working I have to pull the shifter down to 2nd gear manually and take off in 2nd and then shift it into drive manually.After you get going it will not shift into OD.also it will not shift into 1st gear manually.When the OD switch is working (on and off) it will shift ok in drive. It has no pattern as to when it will or will not work. Some days it might shift ok all day long. Sometimes it may not work for a week.I checked the fuse, checked for loose connections etc.... I think it has something to do with the od switch or maybe a relay ? I would appreciate any replys or e- mails . I'm all ears!!!!! Thanks Roboto

the vehicle is a 1995 Jeep grand Cherokee,4.0l 4wd

[theFREAKnasty82]

your overdrive/torque converter solenoid is bad. You should have it scanned for trouble codes that may be stored in memory. Another thing that could be wrong is your governor pressure sensor has failed on the tranmission.

[roboto1720]

Originally Posted by theFREAKnasty82

your overdrive/torque converter solenoid is bad. You should have it scanned for trouble codes that may be stored in memory. Another thing that could be wrong is your governor pressure sensor has failed on the tranmission.

Thanks for the info. I heard from some other people who had the same problem down to the tee. They said the TCU (trans control unit) is most likely the problem. That's what fixed theirs. I quess I'll check the TCU and go from there. Thanks again! I will also scan the tcm and see what it comes up with.