Electrical bug... Overdrive Off Randomly turns "on"

[Bobcat698]

98 Quad Cab Dually Auto.

While driving, the truck will randomly light up the "overdrive off" button on the dash and shift out of overdrive, seemingly just for fun.

Any idea what would cause this?

Thanks in advance!

[turbomatt1]

my 95 has about 300k on it now & occaisionally, will do the same thing. I simply ignore it, as I have a manual switch for lock & od, but if I had to guess as to the actual culpret, I would start at the BCM conector (Body Control Module) & then move over to the conections in the relay box. The Ign. switch is the next thing that comes to mind.
let us know what you find.....

[jambbii]

Trans temp sensor could be bad or your tps could need some cleaning.

[turbomatt1]

yup...Trans temp sensor could be it as well. it makes the BCM turn OD off when trans temp is too cold or too hot. Clean that conection as well before replacing the sensor.

[DONK78]

This is exactly where mine started, then stared kicking out of lock up. I thought it may be the trans temp but that was not the problem. Next time it happens try and pull over and see if you can get it to throw a code for you. If it is the trans temp that is a cheap fix 50-60$$ I had to replace my entire pcm.