Hyundai Sonata: Brake System / Stop Lamp Switch Troubleshooting

Hyundai Sonata LF 2014-2019 Service Manual / Brake System / Brake System / Stop Lamp Switch Troubleshooting

Troubleshooting

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, ESP OFF light illuminated.

A waveform inspection is performed using an oscilloscope on each part during vehicle acceleration/braking. (Refer to stop lamp switch circuit inspection procedures)

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 , ESP 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 , ESP 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 , ESP 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 , ESP OFF light illuminated.

ABS/VDC control module
(Pressure sensor)

-	Symptom : ESP OFF light illuminated.

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	Inspect waveform using an oscilloscope on each part during vehicle acceleration/braking. (Refer to stop lamp switch circuit inspection Procedures) 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
ESP 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.

Stop Lamp Switch Schematic Diagrams

Schematic Diagram System Circuit Diagram Terminal function TeminalDescription1IGN12Engine Control Module (ECM)3B+4Stop Lmap ...

Stop Lamp Switch Repair procedures

Adjustment 1. Turn ignition switch OFF and disconnect the negative (-) battery cable. 2. Remove the lower crash pad. (Refer to Body - "Crash Pad") 3. Remove the knee airbag. (Refer to Rs ...

Other information:

Hyundai Sonata LF 2014-2019 Owners Manual: Child Restraint System (CRS)
Children Always in the Rear WARNING Always properly restrain children in the rear seats of the vehicle. Children of all ages are safer when restrained in the rear seat. A child riding in the front passenger seat can be forcefully struck by an inflating air bag resulting in SERIOUS INJURY or DEATH. ...

Hyundai Sonata LF 2014-2019 Owners Manual: Warning messages
Shift to P (for smart key system and automatic transaxle) This warning message illuminates if you try to turn off the engine without the shift lever in P (Park) position. At this time, the Engine Start/Stop button turns to the ACC position (If you press the Engine Start/Stop button once more, ...