Hyundai i20 Quiz
Braking System

Stop Lamp Switch Repair Procedures

In this manual: Braking System
General Information — 17Engine Mechanical System — 79Engine Electrical System — 50Emission Control System — 22Engine/Fuel Control System — 107Clutch System — 27MANUAL TRANSMISSION SYSTEM — 21Drive Shaft and Axle — 18Suspension System — 29Steering System — 21Restraint — 41Braking System — 53Body Work (Interior and Exterior) — 190Body Electrical System — 181Heating, Ventilation and Air Conditioning — 58
19steps
~114min
4/5difficulty
Done 0 of 19

ITEM

  1. Turn the ignition key to the OFF position and disconnect the negative (-) battery cable.
  2. Remove the lower crash pad. (Refer to Body - Instrument Panel.)
  3. Remove the knee airbag. (Refer to Retainer - Airbag Module.)
  4. Check the clearance between the stop lamp switch and the bracket.

    Brake light switch clearance: 1.0 ~ 2.0 mm (0.04 ~ 0.08 in.)

  5. If the clearance between the brake light switch and the bracket is not 1.0 ~ 2.0 mm (0.04 ~ 0.08 in.), check the retaining clip and other parts near the brake light switch.
  6. If everything is normal, remove the brake light switch and install it again.

Inspection

1. Check the fuses. Install a test fuse on the fuse and check the fuse part to confirm normal sealing adjustment.
2. Analyze GDS data
  1. Analyze GDS data and check if anything is wrong other than the brake light switch.
    1. Connect the GDS to the self-diagnosis connector.
    2. Turn the ignition on.
    3. Press the brake pedal.
    4. Check the "Brake Switch" category displayed on GDS. (Refer to "Data List".) Normal signal waveform: the sensor signal value changes according to the brake ON/OFF switch.
3. Check the connector of each component. Check whether each connector is damaged, terminal overheated, or incompletely connected. [Engine Room Junction Box]
[Brake light electronic module]
[ABS/VDC Control Module]
4. Check the brake light circuit. Connect the probe to each terminal wire and confirm the oscilloscope signal waveform. [Brake light switch input/output]
[Brake light electronic module input/output]
[Oscilloscope Waveform Screen]

DEPOSIT

  1. Turn the ignition key to the OFF position and disconnect the negative (-) battery cable.
  2. Remove the lower crash pad. (Refer to Body - Instrument Panel.)
  3. Remove the knee airbag. (Refer to Retainer - Airbag Module.)
  4. Disconnect the brake light switch connector (A).
  5. Pull the lock plate (A) as shown by the arrow.
  6. Turn the brake light switch 45° counterclockwise and discard it.
  7. Inspect the brake light switch removed according to the procedures described below.
    1. Check the terminal connection is normal.
      • Check that the connector is securely attached and that the locking mark is visible.
    2. Perform resistance inspection of the part.
      Resistance [Ω] 3-4 1/2
      Plunger not protruding
      (OFF)      		 Infinity 0
      Plunger protruding
      (ON)      		 0 Infinity

REMEDY

  1. Attach the brake pedal arm and fully insert the brake light switch as a hidden contact element.
  2. After installation, turn the stop light switch (A) 45° clockwise and press the stopper plate (B).
  3. Check the clearance between the stop lamp switch and the bracket.

    Brake light switch clearance: 1.0 ~ 2.0 mm (0.04 ~ 0.08 in.)

  4. Connect the stop lamp switch connector.
  5. Install the knee airbag. (Refer to Restraint System - "Knee Airbag Module")
  6. Install the lower instrument panel. (Refer to Body - "Instrument Panel")

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