Transmission goes in and out of neutral while in drive, codes P0850 and U1900

KAIUNGERER

MEMBER
2010 FORD TERRITORY
4.0L
6 CYL
2WD
AUTOMATIC
155,000 MILES

My 2010 sy Ford territory has had a lot of problems first it was going into limp home mode the vehicle spent 3 months at an auto electrical mechanic they pointed me in the direction to replace the ECU transmission inhibitor switch and 3 solenoids in the transmission. Since then I have replaced the ECU and done a transmission service while also replacing the 3 dud solenoids within the transition and the inhibitor switch and now the vehicle is dropping in and out of neutral while in drive. No engine light, no transmission codes, nothing.

I have just scanned the car again and it bring up a p0850 park/neutral safety switch code, a u1900 code wich is a manufacturer specific code and 2 others one for fuel level sensor and one for knock sensor short circuit.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

This sounds like a fluid issue so the fact that you just changed it, I am thinking that the fluid is low. Does this issue seem to happen more when taking curves, sitting on a hill, or accelerating?

If so the fluid is what would know you are not flat on the ground so it is going to go to one side of the pan away from the pickup and so it sucks air.

Let's check the fluid level and I would suggest trying to just put another quart in the unit just to make sure. Below is the process to check the fluid on the USA version of your vehicle.

Please let us know what you find with this. Thanks

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