Replacement of the brake light (brake pedal position) switch on a 2024 Model 3 Long Range. The switch sits at the top of the brake pedal bracket under the driver-side dash and clips into a manufacturer-specified retainer.

Warnings

Tools required

Parts

• Brake pedal position / brake light switch × 1 — OEM Tesla Model 3 brake light switch — order by VIN

Preparation

1. Park on level ground, place in P, engage parking brake.
2. Exit ALL doors with the key fob/phone key away from the vehicle. Wait at least 2 minutes for HV systems to fully de-energize, even on this non-HV job.
3. Disconnect the low-voltage battery: on most 2024 Model 3 vehicles the 12V (or Li-ion LV) battery is accessed behind the right rear seat back panel; some 2024+ units have a lithium LV battery under the floor. Confirm location for your specific build before removal.
4. DO NOT touch, cut, or pierce ANY orange cable — these are high-voltage and lethal.
5. If you encounter any orange cable, HV component, or are unsure if a system is de-energized: STOP and consult a Tesla-certified technician.
6. Slide the driver seat fully rearward and tilt the steering wheel up/away to gain access to the brake pedal area.
7. Place a clean shop towel on the driver floor mat to catch dropped fasteners and to kneel on while working under the dash.

Procedure

1. 1

   Locate the brake light switch
   Lying on your back in the driver footwell with a headlamp, locate the brake pedal arm where it meets its pivot bracket on the firewall side. The brake light switch is mounted on the bracket above the pedal, with its plunger contacting a tab on the upper part of the pedal arm. A two- or three-wire low-voltage harness connector plugs into the rear of the switch.
2. 2

   Inspect mounting style before removal
   Tesla Model 3 brake switches are a quarter-turn / clip-in style retained in a plastic carrier on the pedal bracket. Visually confirm the orientation of the retention tabs and the alignment keyway BEFORE attempting removal. Photograph the installed position and harness routing for reference.
   ⚠Do not pry on the switch body with metal tools — the housing is thin plastic and will crack.
3. 3

   Disconnect the switch harness
   Depress the locking tab on the LV connector and gently pull the harness straight off the rear of the switch. If the connector is stiff, work the lock fully open with a plastic pick rather than pulling on the wires.
4. 4

   Remove the old switch
   With the brake pedal at rest, rotate or unclip the switch per its retention design (typically a small counter-clockwise rotation to release the bayonet tabs, or depression of an integrated retaining clip). Withdraw the switch straight out of its carrier. Do not allow the pedal to snap forward against the new switch's mounting hole during the swap.
   ⚠Some plungers are spring-loaded with a self-adjusting ratchet. Once removed, the plunger position cannot be reset — you must install a fresh switch.
5. 5

   Compare old and new switches
   Lay the new switch beside the old one. Confirm identical body shape, plunger length, connector keying, and retention tab pattern. If anything differs, stop and verify the correct part number for your VIN before installing.
6. 6

   Pre-position the new switch
   With the brake pedal in its natural rest position (do NOT press the pedal), insert the new switch into the carrier at the orientation shown by your reference photo. Many Tesla-style self-adjusting switches require the plunger to be fully extended before installation — do not pre-compress the plunger by hand.
7. 7

   Lock the switch into the carrier
   Seat the switch fully and rotate or clip it home per the retention design until you feel a positive detent. The switch must not rock or wobble in the carrier. The plunger should now be in light contact with the pedal arm tab.
8. 8

   Reconnect the harness
   Plug the LV connector into the new switch until the locking tab clicks. Tug-test the connector to verify it is fully latched. Confirm the harness is routed clear of the pedal arm sweep so it cannot be pinched at full pedal travel.
9. 9

   Self-adjust the plunger (if applicable)
   If the switch is the self-adjusting type, slowly press the brake pedal one full stroke and release. This indexes the plunger ratchet to the correct rest position. Do not press the pedal until the switch is fully locked into its carrier or the adjustment will be wrong.

Reassembly

1. Verify the harness clip is fully seated and the switch is locked in its carrier.
2. Confirm no tools, fasteners, or trim pieces remain in the driver footwell.
3. Reconnect the low-voltage battery (negative terminal last if applicable). Torque the 12V terminal to OEM specification — refer to Tesla Service Manual.
4. Reinstall any access panel or seat back panel removed to reach the LV battery.
5. Allow the vehicle to wake fully — the touchscreen may take 30–60 seconds to boot and the BCM may run a self-check.

Verification

• With the vehicle awake and in P, have a helper press the brake pedal while you observe the rear brake/tail lights — both outboard brake lights and the high-mount center stop lamp must illuminate immediately on pedal application and extinguish immediately on release.
• Check the touchscreen for any 'Service Vehicle Soon', 'Brake System' or Autopilot-related alerts. No new alerts should be present.
• Confirm the vehicle will shift out of Park only with the brake pedal pressed — if it shifts without pedal input, the switch is not reading correctly and must be reseated.
• Take a short test drive and confirm: (a) regenerative braking behavior is normal, (b) Autopilot/TACC engages and disengages cleanly on brake tap, and (c) no brake-related warnings appear after a full drive cycle.
• Service interval reminder: while under the dash, this is a good time to note brake fluid age — Tesla recommends DOT brake fluid replacement every 2 years regardless of mileage, and cabin air filter replacement every 2 years.

More procedures for this vehicle