Ok guys I need your help in finding what is wrong with my 1996 Deville.
It is a 1996 Deville with N* with 96K miles. The problem is that it seems to stay in 2nd gear and never shifts. I know what you are thinking Shift Soleniods, right? Please read on.
Now I have changed shift soleniods before, it was on my 94 Concours and it worked fine afterward.

Now is where it gets strange. I have not once received any codes or the CEL light to come on. The problem acts just like my 94 did when it was shift soleniods. However, my 1996 has no had the Check Engine Light come on. Normally, in my experience the shift solenoids would trigger the CEL. Since I am not getting a CEL light could it still be the solenoids causing it not to shift?
Is there anything else that could cause it not to shift? Should I remove the pan and check for V at the solenoids? What should the V be and where to check on the SS harness? I am just not sure where to go since it acts like shift solenoids but won't send out a code. I would greatly appreciate any help on this matter.

I would still check the solenoids. The CEL might not come on yet because your solenoids may not be broken off completely yet. Sometimes the base cracks on the solenoid causing it not shift when the computer sends it the command but it doesn't trigger the light.

Ok, I will. I ordered a new set today and got all of my filters and tranny fluid together. I hope it is the solenoids. Thanks.

Addison is absolutely right. A lot of people had no indicator light when the solenoids failed.

Thanks guys. I will let you guys know. My solenoids are coming in tomorrow and I will install them. Thanks Again.

What are the odds of 2 solenoids going out though? Are you sure it doesn't shift from first to second?

If it really is stuck in second, I'd suspect a wiring or connector problem. Check the 10amp fuse D1 (may be different in your car, this is for a 94). Check the transmission connector (disconnect and reseat it).

The failure of only one solenoid could cause that problem. Replace both but both do not have to be failed to cause it to not shift out of 2.

The failure of only one solenoid could cause that problem. Replace both but both do not have to be failed to cause it to not shift out of 2.

1st gear- A on B off
2nd gear- A off B off
3rd gear- A off B on
4th gear- A on B on

if sol A is dead, you have no first gear, it starts in second, and shifts to third, and stays in 3rd.

If sol B is dead, you have first gear, second gear, but no third gear or fourth gear.

If both Sol A and B are dead, you have second gear only.

This is why I asked if he had first gear or not... Having both fail would be something like a 0.0001% chance. But sometimes it is hard to tell when a shift occurs, especially with a caddy.

it also may have a second gear start/traction control feature that I am unaware of.

Oh, just remembered - I think you can manually run through the gears to find the culprit via the instrument panel diagnostics.

Thanks for the info. Where is the transmission connector? Is it right above the pan outside the trans?

Thanks for the info. Where is the transmission connector? Is it right above the pan outside the trans?

It should be just in front of/below the shift arm linkage on top of the trans. Big round grey 14+ pin connector. Can't miss it.