Steady O/D OFF light on (solid not flashing) and no O/D KZJ78

[BurnsTACP]

Hopped in the truck the other day and the wife had failed to tell me there was a light on on the dash. The O/D OFF light is on steady, and the overdrive won't engage. I haven't noticed any other issues.

I've found threads that talk about a flashing light, but that doesn't pertain to mine. Any ideas as to what the issue is?

 

[GTSSportCoupe]

Check the button contact with a multi-meter to make sure it's working? Will have to look at the wiring schematics to figure out where you can access it. My guess would be at the ECU connectors.

Other guys have had ECU leaking capacitor issues, as well as transmission solenoid issues that have caused transmission problems.

 

[BurnsTACP]

I just had the ECU rebuilt about eight months ago. Hopefully it hasn't spoojed all over itself again. My bet is a solenoid due to age and conditions. I'll report back when I have more data.

 

[AirheadNut]

I had trouble with the O/D solenoid in mine, but the light stayed off. The trans would just shift out of overdrive. When the solenoid fails the light won't necessarily come on, because O/D can be off without the button being pressed (like when the trans kicks down at full throttle).