Stuck in Park story and answers
I'm posting this reply because I experienced this issue yesterday, and solved it. I found there are many posts in this forum on this topic, and there is a lot of speculation, mis-information, and some just plain wrong information about this problem, which can lead readers astray, or even cause additional damage to the vehicle; not to mention, not solving the problem.
Being stuck in park can be a very frustrating and potentially expensive experience. The primary cause, the only one I am familiar with, is a failure to energize the solenoid that is part of the gearshift selector switch that keeps the shifter locked in park until the ignition is turned on and the brake pedal is depressed.
The brake light circuit energizes the solenoid when the selector is in park and the brake lights are energized. A fault in the brake light circuit that blows the fuse that protects the circuit will result in a failure to energize the solenoid. The fuse is fuse number 1, 15 Amps, blue-colored. It is found in the fascia fuse panel at the bottom of the primary fuse block.
Another reason for a failure to energize the solenoid is a faulty brake light switch.
Finally, the solenoid itself may be faulty.
My understanding of the likelihood of these failure modes is that a brake light circuit short is most likely, followed by a bad brake light switch, and then the solenoid.
If the fuse is blown, it is most likely because there is a fault in the circuit. If this is the case, shorting the rear window heater circuit to the brake circuit, as recommended elsewhere, may result in damage to the wiring. Don't do this unless you are certain that the brake light switch is at fault.
What to do:
1. Check brake lights. Are the brake lights working? If so, the problem is probably the solenoid or intervening wiring. Go to (4.) below.
2. If the lights don't work, check the fuse (fuse #1). If the fuse is blown, it's probably a short in the brake light circuit.
Eliminate the likely source of the fault, the tail light assemblies, replace the fuse and try again. Here's how:
I recommend opening the rear light access panels, as when replacing a bulb, and unplugging the wiring harnesses connected to the tail light assemblies. Then replace the fuse, turn the ignition to "run" (position II) step on the brake and try to move the shifter. There should be a spare fuse and a fuse puller tool in the fascia fuse block area. If this works, remember, no tail lights! Have the truck towed, or carefully drive home or to a shop.
3. If the fuse isn't blown, it may be the brake light switch. This circuit may be shorted in order to shift out of park. To do so, remove the kick panel above the brake pedal, and look up the pedal are. The bottommost switch, the one with a hose connected, is the cruise control switch: leave it alone. Above that is the brake light switch. Carefully unplug the four pin flat connector. The switch may come out. On the wire side of the connector there are two wires that are mostly green in color. Prepare to short these wires' connector pins together with a paper clip or something. Set the parking brake, ignition on "run," short the pins and hear a "click;" have an assistant move the shifter out of park (or figure out how to do it yourself!).
4. If all else fails, one may directly energize the solenoid. I did this. It requires removing the center console. Once removed, reconnect the parking brake linkage(!) and locate the connector at the rear of the selector assembly. It is a six (6) contact connector. Disconnect and locate pins 2 and 5, which, if you look into the connector end held horizontally, are the two pins in the center vertical column. Note also that the wires connected to these pins are red and black, respectively. Attach clip leads to the two pins and apply 12 Volts across the leads; polarity shouldn't matter, but I followed the wiring diagram with +12V on pin2 and ground on pin 5. Hear a click, and move the shifter out of park. If there's no click, the solenoid is at fault.
5. Faulty solenoid. I am told that if the shifter assembly is further disassembled, that you can get to the solenoid and manually disengage it; however, I haven't investigated this myself.
Good luck. I personally did this using method 4, before I realized I could have simply unplugged the tail lights. My right tail light was shorted due to severe corrosion. I cleaned it up, replaced the bulb holder, put everything back together, and I'm on my way.
Some parts of this note are somewhat speculative, so proceed with caution.