My 1997 corolla will not shift into overdrive on 1997 Toyota Corolla

I have a 1997 corolla that shifts thru all the gears very good except it will not shift into overdrive

Asked by for the 1997 Toyota Corolla
I had this same problem and the fix was easy. Our thermostat was stuck open and the car wasn't getting up to temperature. Until the car gets up to temperature, it won't shift into overdrive. If your temperature gauge only moves when you are in stop ang go traffic, change the thermostat and you should be good.
1 more answer
Is the OD switch on?