The brake transaxle interlock light came on so I looked at the manual and did what it said. all the transmission leaked out when I did that. now it will stop moving all of a sudden so I add transmission fluid to make it home. what could be the problem that I caused but doing that? is it a easy fix and what needs fixed?

shift interlock system , it's a electrically controlled safety system , won't let gear selector move unless driver pushes the brake pedal . The system has wiring , brake switch , shift lock solenoid . How to Install Replace Shift Interlock Solenoid 1995 09 Ford Ranger Buy...
Check the electrical using a volt meter .
Free wiring diagrams here http://www.bbbind.com/free-tsb Enter vehicle info. Year , make , model an engine . Under system click on transmission / transaxle . Under subsystem transmission controls . Click the search button , then the # 3 blue link. Check fuse's , battery voltage to the brake switch an the brake shift interlock solenoid .

I would say it has something to do with this !
Shift Interlock System An ignition/shifter interlock mechanism is installed to prevent shifting the transaxle out of the PARK position unless the ignition switch is rotated to RUN and the brake pedal is applied. The floor shift interlock system consists of:

• an actuator assembly integral to the ignition/shifter interlock cable assembly.
• a bracket retaining the actuator.
• the necessary wiring.

The solenoid is energized when the ignition switch is turned to the RUN position, locking the transaxle range selector lever in the PARK position. When the brake pedal is applied and the stoplight switch (13480) is activated, the ignition/shifter interlock actuator is deactivated and the transaxle range selector lever can be moved out of the PARK position.

On your vehicle there is a shifter interlock system ,it's a safety feature . Doesn't allow shifter to be put into gear if your foot isn't on the brake pedal .
Visual Inspection Chart Mechanical Electrical

• Transmission shift cable
• Manual control lever
• Transmission control module out of adjustment (6-speed transaxle)

• Fuse
• Connections
• Wiring harness
• Brake pedal position (BPP) switch
• Shift lock actuator
• Transmission control (TC) switch (MKZ)

Diagnostic Trouble Code (DTC) Chart
DTC Component Description Condition Symptom Action B2572 Brake Shift Interlock Brake Shift Interlock Output Circuit Failure The associated circuitry connected to the smart junction box (SJB) or fuse, or the SJB itself may have an issue causing a brake shift interlock concern. Brake shift interlock is inoperative or does not operate correctly. Go To Pinpoint Test A . Symptom Chart
SYMPTOM CHART Condition Possible Sources Action

• Shift interlock system does not release/lock correctly

• Circuitry open/shorted
• Fuse(s)
• Stoplight switch

• Go To Pinpoint Test A .

• Shift interlock system does not release/lock correctly

• Shift lock actuator

• INSTALL a new selector lever assembly. REFER to Selector Lever in this section.

PINPOINT TEST A: THE SHIFT INTERLOCK SYSTEM DOES NOT RELEASE/LOCK CORRECTLY Test Step Result / Action to Take A1 TEST THE BRAKE LIGHTS

• Apply the brake pedal and view the brake lights.
• Do the brake lights illuminate?

Yes
GO to A2 .

No
REFER to Section 417-01 . A2 TEST SHIFT INTERLOCK ACTUATOR POWER CIRCUIT

• Disconnect: Floor Shifter Harness Connector C3245.
• Key in ON position.
• Vehicles equipped with a 3.0L or a 2.3L engine, measure the voltage between floor shifter harness connector C3245-1, vehicle harness side and ground, while applying the brake pedal.
  
• Vehicles equipped with a 3.5L engine, measure the voltage between floor shifter harness connector C2096-1, vehicle harness side and ground, while applying the brake pedal.
  
• Is the voltage greater than 10 volts?

Yes
GO to A3 .

No
REPAIR the circuit. TEST the system for normal operation. A3 TEST SHIFT INTERLOCK ACTUATOR GROUND CIRCUIT

• Key in OFF position.
• Vehicles equipped with a 3.0L or a 2.3L engine, measure the resistance between floor shifter harness connector C3245-4, vehicle harness side and ground.
  
• Vehicles equipped with a 3.5L engine, measure the resistance between floor shifter harness connector C2096-5, vehicle harness side and ground.
  
• Is the resistance less than 5 ohms?

Yes
INSTALL a new selector lever. REFER to Selector Lever in this section.

No
REPAIR the circuit. TEST the system for normal operation. Don't try to force it , you'll break something !

is it a linkage issue? if the shift lever is working and you can feel the detents, check your fluid make sure it is full and clean, if not you could have internal issues with the trans

Do you have floor console shifter ?
Shift Interlock System A brake/shifter interlock system consists of the following:

• ignition switch (11572)
• brake pedal stoplight switch (13480)
• brake shift interlock module
• brake shift interlock solenoid assembly (attached to key interlock assembly)
• necessary wiring

On floor-shift vehicles, the ignition/shifter interlock cable (3F719):

• locks the floor shift transaxle range selector lever in the PARK position when the ignition switch is in the LOCK position.
• requires the floor shift transaxle range selector lever to be in the PARK position to turn the ignition switch to the LOCK position.

Brake light switch , wiring etc... Do you know how to test automotive electrical circuit's using a wiring diagram an a DVOM -digital volt ohm meter ? Free wiring diagrams here http://www.bbbind.com/free-tsb Enter vehicle info. Year , make , model an engine size . Under system click on transmission / transaxle .Under subsystem click on shift interlock . Click the search button an then the blue link . Test the electrical circuits .
Shift Interlock System An ignition/shifter interlock mechanism is installed to prevent shifting the transaxle out of the PARK position unless the ignition switch is rotated to RUN and the brake pedal is applied. The floor shift interlock system consists of:

• an actuator assembly integral to the ignition/shifter interlock cable assembly.
• a bracket retaining the actuator.
• the necessary wiring.

The solenoid is energized when the ignition switch is turned to the RUN position, locking the transaxle range selector lever in the PARK position. When the brake pedal is applied and the stoplight switch (13480) is activated, the ignition/shifter interlock actuator is deactivated and the transaxle range selector lever can be moved out of the PARK position.

Symptom Chart-External Controls
Use Rotunda 73 Digital Multimeter 105-R0051 or equivalent to perform pinpoint tests.
Symptom Chart-External Controls Condition Possible Source Action

• Shift Interlock System Does Not Release or Lock Properly

• Circuitry open/shorted.
• Blown fuse.
• Damaged stoplight switch.
• Damaged ignition/shifter interlock cable.

• GO to Pinpoint Test A .

It will be in your engine compartment. It will be a black box, pull the lid on it. On the inside cover of the lid it will tell you what each fuse is for. Find the fuse that says something to do with rear brake lights. When you replace the fuse make sure it it the exact same size, like replace a 5amp fuse with another 5 amp fuse. Also when you look on the inside cover of the fuse box lid there should be a couple empty spaces with fuses in them, these are spare fuses for your car. You can use one of these but just make sure to replace it.

The first thing I would do is check the transmission fluid level.

The unfourtunate thing on these certain cars they are very notorious for having transmission problems. I am sure it is nothing you have done wrong, Ford had a lot of issues with their transmissions through those years.

I hope this helps, Allen

Maintenance: Normal Service 10000 MI or 16000 KM
Check
Brake Pad.............................................................................................................................................................................................. ____
Diagnose/Test
Data Link Connector............................................................................................................................................................................. ____
Check Diagnostic Trouble Code Memory. Purge if necessary, where applicable.
Vehicle.................................................................................................................................................................................................. ____
Road Test - Check braking, kick-down, steering, electrical, heating & ventilation systems, air
conditioning, and power accessories.
Inspect
Battery................................................................................................................................................................................................... ____
Check electrolyte level. Add if necessary.
Brakes and Traction Control................................................................................................................................................................. ____
Check for damage and leaks.
Constant Velocity Joint Boot................................................................................................................................................................ ____
Coolant.................................................................................................................................................................................................. ____
Check fluid level & add if necessary.
Exhaust System..................................................................................................................................................................................... ____
Check for damage and leaks.
Lighting and Horns............................................................................................................................................................................... ____
Check the lights.
Manual Transmission/Transaxle........................................................................................................................................................... ____
Check shift and clutch interlock.
Shift Interlock, A/T (Vehicle with Automatic Shift Lock (ASL).)....................................................................................................... ____
Check operation, including the park/neutral position switch (where applicable).
Tires...................................................................................................................................................................................................... ____
Check condition and pressure, including spare.
Windshield Washer Reservoir.............................................................................................................................................................. ____
Check fluid level & add if necessary.
Lubricate
Doors..................................................................................................................................................................................................... ____
Replace
Engine Oil............................................................................................................................................................................................. ____
Oil Filter, Engine................................................................................................................................................................................... ____
Reset
Service Reminder Indicators...............................................

Hello Joe...The Aveo has had it shares of problems, and this is one of them....NHTSA issued several bulletins on the 04 Aveo...this following is the one pertaining to the shift interlock.....

Make : CHEVROLET Model : AVEO Year : 2004
Manufacturer : GENERAL MOTORS CORP.
Service Bulletin Num : 070730007 Date of Bulletin: APR 01, 2007
NHTSA Item Number: 10022265
Component: POWER TRAIN:AUTOMATIC TRANSMISSION
Summary:
AUTOMATIC TRANSAXLE/TRANSMISSION SHIFT LEVER MAY NOT SHIFT OUT OF PARK (REPLACE BRAKE TRANSAXLE SHIFT INTERLOCK (BTSI) SOLENOID). *KB

Take that bulletin number to your dealer and see if they can help.

Untill you can get it repaired heres a little tip for getting it out of park....There is a a little hole in front of their gearshift lever that can correct the problem, temporarily. It should say "brake interlock release" or something like that. With car running, put a key-size object into it and push down while moving the lever. It does not damage the transmission, it just releases the lock. (make sure your foot is on the brake)

Now for the brake light issue...do you have power at the switch you replaced? If so go to the relay and check there...if no power there it's probably a bad ground.

Also...you may or may not know, but the timing belts on these Aveos are prone to failure at aprox 50k ...these failures have caused severe engine damage.
Good luck...i hope the information i've provided you find useful.
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