For the past couple months I've been having issues with the shift interlock not releasing the shifter on my 08 F150 STX 4.6. I have searched and searched the internet for a solution to the problem and came across several posts here that have awesome suggestions and fixes that worked for others. I was having issues with the brake lights intermittently working and not working, this was a loose fuse I found, however, this wasn't the cause of my interlock problems as they continued. Next I replaced the stop lamp switch thinking maybe it was a bad connection inside the switch, this again was not the problem. After trying those and having limited time to truly diagnose the issue I just began leaving the truck in neutral and setting the emergency brake, leaving the key in the ignition wherever the truck was (bad idea I know). Today I decided to start troubleshooting the issue as I had some time. I got my tester and started at the fuse box, had power to the fuse. Continued to the stop lamp switch, had power there also. I then removed the airbag, steering wheel, clockspring, and bracket to remove the shift lock solenoid, I replaced the solenoid with a new one from my local ford dealer and put the truck back together, thinking that had to fix the problem. Wrong, still no go, still will not shift from park. This one does have a working manual override though which helps alot, the override on the old solenoid broke off. I didn't test the connections for power near the solenoid, just forgot to when I had it disassembled and plan on doing it this weekend. Other than maybe a short near the connection to the solenoid is there something I am missing? Maybe something I am overlooking that you guys can help me with?

 

Bump.

 

Brake pedal position sensor. Had this happen my self, tail lights wouldnt light up unless i really stomped the pedal, and then i could shift out of park. The sensor controls the lock in the shifter. Autozone like 20 bucks

 

As far as i can tell, there is no brake position sensor (im taking it your refering to the sensor on the master cylinder of older models.)

 

The pressure switch you're referring to on older model F-Series was the Speed Control Disengage Switch. That does exactly what it says...disengages the cruise control when the brakes are applied. The actual brake switch is under the dash where the pedal is attatched to the frame of the dash. Replacing that should solve your issue.

 

Did you ever fix this?
What was it?
thx