How do I change the shift interlock actuator on a 99 ford ranger?

Safety system - shift interlock . Won't let driver move gear selector unless foot is pushing on the brake pedal . part's involved (FEM) front electronic module , brake switch .
Shift Interlock System
The shift interlock system consists of:

• a shift lock actuator .
  • A transmission shift lock actuator, which clips to the actuator retainer, securing the shift lock actuator to the steering column.
  • A transmission shift lock actuator cable which routes to the floor console mounted shifter assembly lock mechanism.
• electrical circuits to supply power to lock and unlock the shift lock actuator.

The shift lock mechanism locks the gearshift lever in PARK:

• when the ignition switch lock cylinder is in the LOCK position.
• with the ignition switch lock cylinder in the RUN position and the brake pedal released.

The shift lock actuator releases the gearshift lever:

• when the ignition switch lock cylinder is in the FIRST position.
• with the ignition switch lock cylinder in the RUN position and the brake pedal actuated.
• '
• does your car have column or floor console shifter ?
• SYMPTOM CHART Condition Possible Sources Action
  • The shift interlock system does not release/lock correctly
  • Circuit(s).
  • Fuse(s).
  • Shift lock actuator.
  • Brake pedal position (BPP) switch.
  • Go To Pinpoint Test A .
• your best bet maybe to take your vehicle to a qualified repair shop., unless you know how to diagnosed automotive electrical circuit's , viewing wiring diagrams an testing with a DVOM - digital volt ohm meter . Do you know what an automotive electrical wiring diagram is ?

If this is a clutch then you need to look into the shift actuator is what I believe it is called. It is a located on your clutch pedal. If this is an automatic it still could be something similar to that.

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Shift Interlock System
The shift interlock system prevents a shift out of PARK unless the brake pedal is depressed. The shift interlock system has a shift lock actuator mounted on the floor shifter assembly. If the ignition switch is in the RUN position, the shift actuator will allow the shifter to be moved out of PARK only when the brake pedal is pressed.
Electroniclly controlled !

Condition Possible Sources Action

• The shift interlock system does not release or lock correctly

• Fuse in battery junction box (BJB)

• Check fuses.

• Brake pedal position (BPP) switch

• CHECK the BPP switch. REFER to Section 206-09 .

• Floor shifter wiring and/or connectors
• Transmission selector lever
• Ignition system

• Go To Pinpoint Test A .

Check to see if you have brake lights if not fix the switch on brake pedal. If yes you need to look at the shift interlock system, normally a little white box just below the key on the column. On fords you can put key in and turn a little bit so it's straight vertical and shift to neutral then start it. Your problem is with the shift interlock system that gets activated with the press of brake pedal

THE SHIFT INTERLOCK IS LOCATED ON THE STEERING COLUM

2wd or 4wd?
shifting what, A/T M/T or 4wd.?
try to say what you have first then post a question specific to a part.
are you inside the tranny or just inside,car.???
her are lots of interlocks,
my wild guess, is a/T park lock circuits and parts. right?
inside car?

column or floor shifter ?
Brake Shift Interlock Actuator - Floor Shift Removal and Installation
NOTE: The brake shift interlock actuator is not serviced individually. If replacement is required, install a new floor shift selector lever assembly.
For additional information, refer to Selector Lever - Floor Shift in this section.
Brake Shift Interlock Actuator - Column Shift Removal and Installation

1. Set the parking brake.

1. Remove the steering column shrouds.

1. Turn the ignition to the accessory position and apply the brake or actuate the brake shift interlock actuator (BSIA) override.

1. Put the selector lever into the NEUTRAL position.

1. Disconnect the BSIA electrical connector.

1. Remove the BSIA screw.

1. Gently pry the clip up and remove the BSIA.

1. NOTE: During installation, verify that the BSIA override has been activated and the slider is fully rearward. Before rotating the selector lever from NEUTRAL into PARK, align the selector lever tab into the BSIA. To install, reverse the removal procedure.

The shift interlock system prevents the shifting from PARK unless the brake pedal (2455) is depressed. The shift interlock system consists of a shift lock actuator (3Z719) mounted at the base of the steering column tube (3514). If the ignition switch (11572) is in the RUN position, the shift lock actuator is continually on unless the brake pedal is depressed. The shift lock actuator is the logical culprit. Check to see if it's getting voltage when the brake pedal is depressed. If yes: the unit is either faulty, weak or stuck. I can provide wire numbers and colors if necessary. I may need the engine size and Trans. code found on drivers door sticker. Good luck! Aoogha

Shift Interlock System
The shift interlock system prevents the shifting from PARK unless the brake pedal (2455) is depressed. The shift interlock system consists of a shift lock actuator (3Z719) mounted at the base of the steering column tube (3514). If the ignition switch (11572) is in the RUN position, the shift lock actuator is continually on unless the brake pedal is depressed.

Thier is also the shift lock actuator ! plus wiring . You have a short to ground on that circuit . Do you know how to Find a short ? videos on youtube .
None of the power windows work ? Check for broken wires inside the rubber boot from the body to drivers door !
Videos on youtube for testing power window circuits .
How to test power window switch motor 1985 2001 Toyota