My 97 auto isn't shifting into overdrive. It has been down for a few weeks to install a new hvac box. Got it back together today, took it for test drive, worked great. Parked it for an hour and now it won't shift into OD. It behaved the same way before I tore it apart.
Is this electrical? Maybe a sensor? All of the connections seem to be ok. Is there a shift solenoid for OD? Did unplugging the battery reset the computer? The tranny shifts great otherwise. Also there are no codes or check engine lights.

 

Brake pedal switch is the first place I'd look.

 

Really. K I'll check it out. Thanks

 

A quick way to check the brake switch is to see if the cruise control works. If it works the brake switch is fine. If you don't have cruise, stick your head up under there pump the brake and you should be able to hear the switch working.

 

Cruise is working fine, but the switch doesn't click or make any noise for that matter. I can press the button all the way in with my finger, no click.

 

If the brake lights and cruise are working fine and fluid is ok, I guess you could check the TV cable (kick down cable adjustment) otherwise, I'm out of things to try other than sensors.

 

It was never designed to 'click'.


Here's test procedures for the brake lamp switch. Terminals 1 and 2 are the switch for the TCM (OD).


It is possible to have cruise control and stop lamps work but not the TCM switch.









Brake Lamp Switch circuit: The brake lamp switch is shown in the brake NOT applied position. The TCM Brake Lamp Switch Sense input is looking for a ground, when the brake is applied the ground is removed - no OD.



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Ken to the rescue !

 

The cable was out of adjustment. The previous owner did a number on this thing. I have a list of things a mile long that were done poorly by the fellow. Thanks for the help!

 

glad to help !

 

For those thinking WTF is the TV cable.. here is a vid