Strange problem with overdrive switch and cruise control...1995 Ford E250 van

I have had an intermittent problem with my van’s cruise control for almost 10 years now. I’ve never tried to have it fixed, because I have NEVER been able to MAKE it happen. Intermittent doesn’t even begin to describe it. I once drove it all the way to Massachusetts with no problems, and on the way back got to Virginia before it popped up. On the other hand, I’ve had it happen before I get to the end of the road I live on and I wasn’t even using cruise control at that time!

Here’s what happens: I’ll be driving along just fine on cruise control (and occasionally not), and suddenly the cruise control will cut out and the “Off” light on the end of the shift lever will start blinking…as if I had pressed the “Overdrive” switch. But I can’t turn off that “Off” light and as long as it is blinking the cruise control will not work, and the transmission makes a “roaring” sound as it’s about to shift up or down, and when it does shift it literally SLAMS into gear.

Sometimes I can fix the problem by stopping, cutting off the engine, and starting again…but mostly that doesn’t work either. If I just continue to drive, and put up with the strange shifting…the “Off” light on the shifter will eventually go out and then I can use cruise control again, and shifting goes back to normal.

I have no problems at all with the way the transmission shifts under normal circumstances…though there IS a slight hesitation in the engine when it down-shifts going up hills, but it’s always done that, even when it was brand new. So I haven’t worried about it overmuch.

Anyway, I’m working on getting this van back into good working condition and I’d like to get my cruise control problem fixed. Anyone got ANY ideas what that problem might be, so I can at last give my mechanic something to aim at?

Quite possibly a problem with the Vehicle Speed Sensor or the wire connector that it’s attached to.
The VSS is located on the left rear of the transmission on the extension housing and it’s easy to change.

When the ‘O/D Off’ is flashing, the Transmission Control Module has detected a fault. Since this transmission is electronically shifted, a fault is a serious problem. The cruise control will be disabled if the transmission is in ‘limp mode’.

Consider yourself lucky the transmission hasn’t self-destructed yet. Take it to a transmission shop to get any codes read that could be stored in the TCM. It could be a fairly inexpensive fix.

The first thing I get suspicious of for these kind of issues is wiring problems, especially in the power circuits. A relay problem is another possibility. Hopefully there will be some good clues taken from the error codes.

And the winner is…ok4450! At least, my mechanic found a speed sensor that wasn’t registering correctly and he replaced it. We’re not sure it was the cause of the problem yet…but time will tell!

Hope that takes care of it and thanks for the update.