Hi

I got a problem with my 08 Navigator. wrench symbol came up and the car has hard time shifting down, it also doesn't accelerate as it should. P1719 code cam up on diagnostic which is overdrive drum speed sensor malfunction.

I got 2 questions, is that the speed sensor which that shows speed on the dash?

And does anyone know where is it located?

Please Help I need the car for work

 

No expert here.
No that is not your speedometer sensor. The overdrive drum is inside your transmission.

I think the overdrive drum sensor is located inside your transmission and it is measuring the rpm of one of the shafts inside your transmission. There are several shafts in your transmission and their rpms vary during driving.

If the shaft rpm is too fast or too slow for the conditions a diagnostic trouble code will be recorded and the powertrain trouble light will appear - the wrench.

As you are noticing, your transmission is not shifting properly. Could be a bad sensor or the sensor is truly indicating a mechanical problem.

I do not know how these sensors are tested. I wish I did though.

Maybe taking the trans out of overdrive when slowing down will help it shift down better until you know just what the problem is.
To take it out of overdrive push the button on the shifter ('07 navigator location - yours could be different). When you take it out of overdrive a light in the inst panel will light up.
Good luck,

Richard