Hello Scotty,
I have a 2011 Ford F-150 XLT with a 5.0 engine. It will randomly not start up. Checked the fuse box and the passenger side connector to the dash. When it has this issue, there is a clicking noise coming from both the fuse box under the hood and connectors on the passenger side of the dash. Changed the starter and battery. Didn't fix the issue. Then after messing around with it in the evening, pulled it to the side of my house and stuck the OBD reader. Had a P0905 code about the transmission electrical switch. I unplugged the OBD reader and low and behold started right up like nothing was wrong with it. This is about the third time this happens. Do you have any suggestions? Thank you in advance for your help!
Thank you,
Roger
The symptom that your truck doesn't display which gear it's in points to the Transmission Range Sensor. That will also cause a No Crank/No Start.
And you may be getting off easy because it could be a lot worse.
In 2011 they redesigned the Molded Lead Frame on the 6R80 transmissions. They took the TCM out of it (good idea) but they screwed up the new design and there were problems.
Here's what it looks like:
On yours it sounds like that transmission range sensor is acting up. (black part that slides back and forth in that tan carrier).
Your 2011 didn't come with that foam strip around the contacts which the solenoids plug into. They were having problems with metal particles getting between those contacts and shorting out so they added the foam strip to keep that stuff out of there.
But the worst problem is with the Output Speed Sensor. It's mounted on the other side of the molded lead frame. This is why I made the comment "you may be getting off easy"
The problem was that the sensor would intermittently fail and stop sending the vehicle speed to the computer.
When the computer lost the vehicle speed reading it assumed the truck wasn't moving and put the truck in 1st gear.
Ford described it as "an unintended downshift into first gear".
In reality, guys were cruising down the highway at 60 mph and out of nowhere the truck would drop down into 1st gear and lock up the back wheels. Bad enough in the best of circumstances but imagine being on a congested highway, maybe towing a trailer, and having that happen.
Ford addresses this one in "Customer Satisfaction Program 16N02"
https://static.nhtsa.gov/odi/tsbs/2016/SB-10091155-5448.pdf
If your truck hasn't had the updated Molded Lead Frame put into it you should consider doing it and it will probably fix your No Crank/No Start problem
Are you saying that you can replicate the OBD start trick? Were you able to do that on the three times it happened?
I wonder if there is a loose connection somewhere, which by accessing the OBD connector, jiggled the connection ON? Otherwise, I don't quite see how accessing OBDII would "fix" anything.
Some cars have relay that sends the power to the starter solenoid. Have you checked that relay, if there is one?
There is a relay. This morning started right up but the needle that shows the position on the dash doesn’t show also. Turned it off and started doing the same thing. Also, the wrench symbol came up on the dash. Could it be the electrical part on the transmission?