Automatic - won't go to gear

[txiong]

My friends Jetta will not go into gear when in park. This doesn't happen every time. It'll do this once in awhile. There's a picture of a foot by the gear shifter and you can't switch gear until the light on that picture goes off. You'll have to depress brake pedal until that light goes off then you can switch gears. This leads me to think that there's a switch that is faulty. But I wanted to know if anyone has expierenced this before. If so where is the switch located? I'm thinking it maybe by the gear shifter because I can hear a clucking/clicking noise when the brake pedal is depressed. Oh, and the brake lights work fine even when it's not allowing you to switch gears. Thanks in advance and if possible email me your opinion or solution.

[boschmann]

It's called a shift lock. It shoul do it every time. Any newer vehicle requires you to put your foot on the brake before leting you shift out of park. This all started back with the mid 80's Audi's, which were blamed for involuntary acceleration/takeoff when shifted into gear.

[txiong]

So I'm guessing that the shift lock is located by the gear shifter. But is it the shift lock that's defective or is it a switch for this? And if there is a switch is it by the brake pedal?

[boschmann]

I take it that at times you press the brake and the light doesn't go out and you can't get out of park. What year is the car? All I need to know is '98 or earlier of '99 or later.

[txiong]

Shoot. I don't even know what year it is. I'll find out though. Thanks.

[txiong]

It's a 99' Jetta

[boschmann]

Because you say you hear a clunking at the shifter it sounds like there might be some physical jamming of the shift lock solenoid (at the shifter) or the solenoid itself may be bad. Before replacing it you may want to check a few things, hopefully you can make a drawing from this description. You can adequately perform these checks with a test light. A multimeter will give you actual voltage readings, which can warn you of excessive resistance in a wire.

Your solenoid is controlled through the transmission control module or TCM (under the hood at the base of the windshield under the plenum, right side). The signal originates from the brake light switch (above the brake pedal). Fuse #13 gives power to the switch pin#1 (red brown) and when the pedal is depressed it sends the power out pin#2 (red/black) to the TCM pin #15. Since you have brake lights this probably is all working properly, but there is a junction to the brake lights after the switch and if there is a problem at the junction there may not be voltage making it to the TCM on pin #15. Once the TCM receives this signal it will send a ground from pin #29 (brown/blue) of the TCM to pin #2 of the solenoid. The power for the solenoid comes from fuse #11 through a black/violet wire to pin #1 on the solenoid. If you are getting both the "hot" from fuse #11 and the ground signal (when pedal depressed & ignition on) to the solenoid & it will only clunk or do nothing, then I'd try to adjust or replace it respectively. To check for a voltage drop (wire resistance) problem you can try running a ground and hot wire directly to the solenoid & see if it works properly every time.

Unfortunately there is one part of the system I am confused about: The selecter position warning light (LED) tied into the system. It's power comes from fuse #7 (for most of the exterior lights) and it's ground comes from the same wire that goes to the solenoid. That means it would stay off normally and when you depress the brake it would come on signalling you can change gears. That seems reverse to what you said is happening. Hopefully you can find a problem based on my description of how it should be operating that explains this. I have heard the brake switch will stick and cause this type of problem, but you said the rear lights were working properly. Good luck!