Mustang 1999 problem with shift out of park

So? What does that tell you? It's either the brake switch or the associated wiring.

And since you have no brake lights either*******

Hopefully you are not driving the car without brake lights, even if you know how to get around the shift interlock...

start the car, then shift

The brake light switch is also operating a solenoid that locks the shifter. You need to check the switch and it's wiring.

Also, driving without brake lights is both dangerous and illegal.

Not if you roll down the window and signal every stop the good old-fashioned (and still quite legal) way - Left arm out 90-degrees, elbow bent, forearm straight down, palm back.

Been There, Done That. Gotta get to work, I can fix it tonight.

Hopefully the people that end up driving behind you were paying enough attention in Driver's Ed (rather than reading a Playboy stuck inside their textbook) to remember what that means in time. ;-)

If they don't, it's their own damned fault.

Of course, that will get old REAL fast when it gets cold outside, and even moreso when it's below 40F, or raining, or snowing...

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