Hyundai Tucson: Brake System / Stop Lamp Switch

- Components

1. Brake member assembly
2. Stop lamp switch
3. Brake pedal arm assembly
4. Brake pedal pad

- Schematic Diagram

- System circuit diagram

- Terminal Function

Teminal	Description
1	IGN1
2	Engine Control Module (ECM)
3	-
4	B+
5	Stop Lamp
6	Gruound

- Adjustment

1.Turn ignition switch OFF and disconnect the negative (-) battery cable.

2.Remove the crash pad lower panel.(Refer to Body - "Crash Pad Lower Panel")

3.Confirm the gap between stop lamp switch and bracket.

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

4.If the gap between stop lamp switch and bracket is not 1.0 - 2.0 mm (0.04 - 0.08 in), check the mounting clip and other part of around stop lamp.

5.If there is normal, remove the stop lamp switch and then install again.

- Inspection 1. Fuse inspection Mount the test fuse to the switch fuse and relay fuse part to confirm a normal joint fit.

2. Diagnostic tool Data Analysis

1.Analyze diagnostic tool data and confirm if there is anything wrong with the stop lamp switch.

(1) Connect the diagnostic tool to the self-diagnosis connector.

(2) Turn the spark switch on

(3) Step on the brake pedal.

(4)Inspect the "brake switch" category that displays the "sensor data" diagnostic tool.

Normal waveform : The pressure sensor signal value will change according to the brake ON/OFF switch.

3. Inspection of connector by each part Check to see whether or not each connector has been damaged, or terminal surge, or incomplete connection has taken place[Engine room junction box]

[ABS/VDC control module]

4. Inspect the stop lamp circuit Connect probe to each terminal wire and confirm oscilloscope waveform.[Stop lamp switch input/output]

[Oscilloscope waveform screen]

- Removal

1.Turn ignition switch OFF and disconnect the negative (-) battery cable.

2.Remove the crash pad lower panel.(Refer to Body - "Crash Pad Lower Panel")

3.Disconnect the stop lamp switch connector (A).

4.Pull the locking plate (A) as indicated by the arrow.

5.Turn stop lamp switch (A) 45° counterclockwise and remove it.

6.Inspect a removed stop lamp switch along the below procedures.

(1)Confirm a normal connection with terminal part.A confirmation can be made to see if the connector has been secured properly and if a connection mark is present.

- Installation

1.After inserting, turn the stop switch (A) 45° clockwise, and then assemble locking plate by pushing.

2.Assemble the locking plate (A) by pushing it in the direction of the arrow.

3.Confirm the gap between stop lamp switch and bracket.

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

   

• If the gap between stop lamp switch and bracket is not 1.0-2.0mm (0.04-0.08in), perform the above process again.

4.Connect the stop lamp switch connector (A).

5.Install the crash pad lower panel.(Refer to Body - "Crash Pad Lower Panel")

6.Connect the ( - ) battery terminal.

- Troubleshooting

1. Part diagnosis

Items	Cause	Symptom
Switch fuse	Faulty fuse connection, Damaged fuse	– DTC Code : P0504 – Symptom : Shifting gear trouble, Starting failure, Cruise control function cancelation trouble, EPB function cancelation trouble, Stop lamp lighting trouble, ESC OFF light illuminated.	① A waveform inspection is performed using an oscilloscope on each part during vehicle acceleration/braking. (Refer to stop lamp switch circuit inspection procedures) ② Refer to the relevant repair procedures of the part when something abnormal is discovered in the waveform (Refer to the repair procedures of the relevant part and if necessary replace it)
Relay fuse	Faulty fuse connection, Damaged fuse	– DTC Code : P0504 – Symptom : Shifting gear trouble, Starting failure, Cruise control function cancelation trouble, EPB function cancelation trouble, Stop lamp lighting trouble , ESC OFF light illuminated.
Stop lamp switch	• Damaged wiring of each part • Faulty connection to connector • Each part is defective	– DTC Code : P0504 – Symptom : Shifting gear trouble, Starting failure, Cruise control function cancelation trouble, EPB function cancelation trouble, Stop lamp lighting trouble , ESC OFF light illuminated.
Stop signal electronic module (If it applies)		– DTC Code : P0504, C2130, C2131 – Symptom : Shifting gear trouble, Starting failure, Cruise control function cancelation trouble, EPB function cancelation trouble, Stop lamp lighting trouble , ESC OFF light illuminated.
Engine control module (ECM)		– DTC Code : P0504 – Symptom :Shifting gear trouble,Cruise control function cancelation trouble
Body control module (BCM)		– Shifting gear trouble
Shift-lock solenoid		– Shifting gear trouble
Inhibitor switch		– Symptom : Shifting gear trouble, Starting failure, Cruise control function cancelation trouble, EPB function cancelation trouble
Smart Key Unit (SMK)		– Starting failure
Electronic parking brake		– Symptom : EPB function cancelation trouble , ESC OFF light illuminated.
ABS/VDC Control module (Pressure sensor)		– Symptom : ESC OFF light illuminated.

2. Symptom diagnosis

Symptom	Part that could be the cause
Trouble starting	Switch fuse, Relay fuse, Stop lamp switch, Stop signal electronic module, ABS/VDC control module, Each wire, Connector	① Inspect waveform using an oscilloscope on each part during vehicle acceleration/braking. (Refer to stop lamp switch circuit inspection Procedures) ② Refer to the relevant repair procedures of the part when something abnormal is discovered in the waveform (Refer to the repair procedures of the relevant part and if necessary replace it)
Trouble shifting gears	Switch fuse, Relay fuse, Stop lamp switch, Stop signal electronic module, BCM, ECM, Inhibitor switch, Each wire, Connector
ESC OFF light illuminated	Switch fuse, Relay fuse, Stop lamp switch, Stop signal electronic module, ABS/VDC control module, Each wire, Connector
P0504	Switch fuse, Relay fuse, Stop lamp switch, Stop signal electronic module, ECM, Each wire, Connector
Stop lamp does notworking	Switch fuse, Relay fuse, Stop lamp switch, Stop signal electronic module, Wire/Connector disconnected
Stop lamp always turns on	Stop lamp switch, Stop signal electronic module, Wiring short circuit, Damaged fuse

3.Stop lamp switch system diagnosis

SSEM : Stop Signal Electronic Module

4.Refer to DTC guide when the related DTC codes are displayed.