Recently while driving at freeway speeds the vehicle will jerk a bit and the speedometer drops to zero and the wrench symbol comes on. The cruise control doesn't work and passenger airbag becomes disabled as a result. I can keep driving but have no idea how fast I'm going. If I stop the vehicle and turn it off and restart - it goes away and everything returns to normal - until it happens again usually at at later date. My code scanner stores a PO720 code. On older Expeditions - all indications point to the output speed sensor on the transmission. But I cannot find an output speed sensor listed in any parts listing for this year expedition. There are ABS wheel speed sensors and those seem to be working properly (I have a scanner that checks ABS). Looking for 1) where does the vehicle get it's speed for the speedometer? 1) Any ideas on what could be causing this?
Transmission drops to zero - PO720 code
- Thread starter gnapert
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Wish i had better news for you but,
The output speed sensor is in the transmission
Here is Ford Tech Makuloco to tell you all about it.
https://www.youtube.com/watch?v=4Ng3HJdyyoM
This happened in my 2007 and it turned out to be a leaky bulkhead connector, the trans fluid was getting into the connection point which disturbed the connection to the OSS. Unplug that big plug in the back and see if you have trans fluid inside it
Thanks for the tip - will check it out.
