Brake Shift Interlock Solenoid

Hello to all, could anyone tell me what exactly a Brake Shift Interlock Solenoid does, and were it is located. My wife complains that there is a "groaning " noise from under the floor, under the brake pedal area. Then when she shifts from park to rev, fuses blow. Thanks to all. p

What year model?

What number fuse?

Brake Shift Interlock is inside the steering column.
It prevents you from shifting out of Park without your foot on the brake....whenever the engine is running.
I read the instructions.....it is a bear to get at.

HOWEVER, much higher failure is the wire going from the fuse.....to the "Brake On OFF" switch "BOO". I had that happen......while doing another...unrelated repair........
I posted a picture of the BOO switch......at
http://community.webshots.com/album/201931518cScpNK

On my '96....Brake Shift Interlock is Fuse #7.
It is labeled as 15amp on the fuse block.....and on most documentation...on Alldatadiy....but I did find 1 drawing that had it labeled as 10amp.
I had a 10amp fuse there......It has not blown in 9 years of operation.... So I am going to guess that it is the correct value. I do NOT have the trailer tow package.....which might be a factor in the different value. I left mine at the original 10amp.

The Fuse block is located up under the dash.....driver's side......next to the door.

The "BOO" switch is mounted on the brake pedal....follow the shaft up under the dash.....and the switch is mounted at a pivot point on the shaft.
It is possible that the wire broke off.....and is touching something that it should not be.
Also....check your brake lamps....perhaps one of those is blowing the fuse?

If the wire is off the BOO switch....you cannot shift from P with the engine running....and you will NOT have brake lights. You will be able to shift from P by turning the key far enough to unlock the steering column....but not all the way ON.....shift into Neutral.....Start car......you will be able to shift as normal....as long as you do not shift into Park. Do not leave things that way....as driving without brake lights is very dangerous.

Thanks guys!!! The particular car with trouble is my 2000 3.8 LX. I just found that the connector that hooks up to my brake press swt (screwed under the brk master) was scorched/burned, and the large connector that goes to the cruise control module (under the brk master) didn't look blackened, however smelled burned. The press swt seems to have a slow leak.

My #10 fuse keeps blowing [heated backlite (???), speed control, ABS module, cluster, front temp blend door (???) brake shift interlock solenoid, powertrain control module, front a/c control head]

(???)=what in the world is this

So I figured that its gotta be one of those systems that is blowing the fuse. I did disconnect the brk press swt (removed burnt end) and the cruise control connector, however it didn't seem to correct the problem.

I know I will have to do the brk press swt R/R, but I'm still at a lost.

Any other recommendations? Thanks guys, p

The heated backlite (liftgate window) is a good candidate. Also you may have a short in that pigtail that goes to switch on brake master cylinder ..... did you replace the switch.... that is actually "number 1"?

Thanks to all who've helped!!! i changed my battery cable assy. ( $130.00 from FOMOCO. the pos and neg batt cable is 1 pc.) fairly easy r/r, 30 minutes. ran all accy's (a/c, radio, headlites, etc.) no longer have extremely hot batt cable, or blown fuses. i have yet to test it in traffic or long drives. i will have to splice in the new brk press switch, since the original plug was burnt beyong recognition. i'll probably do that when i change the osolator bolts; its hard to fill the brk master. thanks again for all your help. p