Stop Lamp Switch

Components and Component Location

COMPONENTS

1. Stop Lamp Switch 2. Nut 3. Return Spring

4. Brake Pedal Crossmember Assembly 5. Bolt 6. Brake Pedal Arm

Circuit Diagrams

SCHEMATIC DIAGRAM

System Diagram

TERMINAL FUNCTION

Thick head	Description
1	ALL1
2	Engine Control Module (ECM)
3	B.
4	Stop Lamp

Troubleshooting

TROUBLESHOOTING

1. 1
   Diagnostic Procedure

   Item	Cause	Symptom
   Fuse Switch	Loose fuse connection, damaged fuse	DTC: P0504 Symptom: Gear shifting difficult, start failure, cruise control cancel function difficult, EPB release function difficult, brake lights difficult to turn on, ESP OFF indicator light on	① Check the signal waveform with an oscilloscope on each component while accelerating/decelerating the vehicle. (Refer to Brake Light Switch Circuit Inspection Procedures.) ② If anything abnormal is found in the signal, refer to the proper repair procedure for the component (refer to the repair and replacement procedure of the relevant component if necessary).
   Fuse Relay	Loose fuse connection, damaged fuse	DTC: P0504 Symptom: Gear shifting difficult, start failure, cruise control cancel function difficult, EPB release function difficult, brake lights difficult to turn on, ESP OFF indicator light on.
   Stop Lamp Switch	Damaged wiring of each component Incorrect connector connection Each component is faulty	DTC: P0504 Symptom: Gear shifting difficult, start failure, cruise control cancel function difficult, EPB release function difficult, brake lights difficult to turn on, ESP OFF indicator light on.
   Brake light electronic module Shutdown (if equipped)		Diagnostic Trouble Codes: P0504, C2130, C2131 Symptom: Gear shifting difficult, start failure, cruise control cancel function difficult, EPB release function difficult, brake lights difficult to turn on, ESP OFF indicator light on.
   Engine Control Module (ECM)		DTC: P0504 Symptom: Shift error, cruise control cancel error
   Body Control Module (BCM)		Shift failure
   Lock solenoid		Shift failure
   SHIFT LOCK SWITCH		Symptom: Gear shifting difficult, start failure, cruise control cancel function difficult, EPB release function difficult
   Smart Key Unit (SMK)		Start failure
   Electronic Parking Brake (EPB)		Symptom: EPB lock failure, ESP OFF indicator light on
   ABS/VDC control unit [Pressure sensor]		Symptom: ESP OFF indicator light on.

2. 2
   Symptom Diagnostic Procedure

   Symptom	Possible Causes
   Start failure	Switch fuse, relay fuse, brake light switch, brake light electronic module, ABS/VDC control module, each wire, connector	① Check the signal waveform with an oscilloscope on each component while accelerating/decelerating the vehicle. (Refer to Brake Light Switch Circuit Inspection Procedures.) ② If anything abnormal is found in the signal, refer to the proper repair procedure for the component (refer to the repair and replacement procedure of the relevant component if necessary).
   Faulty shift switches	Switch fuse, relay fuse, brake light switch, brake light electronic module, BCM, ECM, shift lock switch, each wire, connector
   ESP OFF indicator light on	Switch fuse, relay fuse, brake light switch, brake light electronic module, ABS/VDC control module, each wire, connector
   P0504	Switch fuse, relay fuse, brake light switch, brake light electronic module, ECM, each wire, connector
   Stop lamp does not work	Switch fuse, relay fuse, brake light switch, brake light electronic module, wire/connector disconnected
   Brake lights always on	Brake light switch, brake light electronic module, wiring short circuit, blown fuse

3. 3
   Stop Lamp Switch System Diagnosis

   

   

   SSEM: Stop Lamp Electronic Module
4. 4
   Refer to the DTC troubleshooting guide when the relevant DTCs are displayed.

Repair Procedures

ITEM

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

   Stop lamp switch clearance (A): 1.0-2.0 mm (0.04-0.08 in.)

   

4. 4
   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.
5. 5
   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]

[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]

[Oscilloscope Waveform Screen]

DEPOSIT

1. 1
   Turn the ignition key to the OFF position and disconnect the negative (-) battery cable.
2. 2
   Remove the lower crash pad. (Refer to Body - Instrument Panel.)
3. 3
   Disconnect the brake light switch connector (A).

   

4. 4
   Pull the lock plate (A) as shown by the arrow.

   

5. 5
   Turn the brake light switch 45° counterclockwise and discard it.

   

6. 6
   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. 1
   Attach the brake pedal arm and fully insert the brake light switch as a hidden contact element.

   

2. 2
   After installation, turn the stop lamp switch (A) 45° clockwise and lift the stopper plate.

   

3. 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. 4
   Connect the stop lamp switch connector.
5. 5
   Install the lower instrument panel. (Refer to Body - "Instrument Panel")