Connect GDS and select "Diagnostic Trouble Codes(DTC)" mode.

Confirm that "DTC Readiness Flag" indicates "COMPLETED". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.

Read "DTC Status" parameter in DTC menu of the GDS.

Is parameter displayed "History(Not Present) fault"?

	▶ Fault is caused by having been repaired and HECU memory was not cleared. Clear the DTC and then go to "Verification of Vehicle Repair" procedure.
	▶ Go to next step.

Connect GDS to Data Link Connector(DLC).

IG "ON".

Press the brake pedal.

Monitor the "Brake Light Switch" parameter on the "Current Data" menu of the GDS.

Fig.1) Pressure Sensor's data is increased with brake switch turning ON when the brake pedal is depressed. (normal)

Fig.2) Stop lamp turns ON with brake switch turning ON when the brake pedal is depressed. (normal)

Fig.3) Pressure Sensor's data is increased while brake switch is shown OFF state when the brake pedal is depressed. (brake circuit error)

Fig.4) Pressure Sensor's data is decreased slowly when the brake pedal is depressed. (pressure sensor fault)

Whenever Brake pedal is pushed down, is the brake lamp switch's GDS data changed ON/OFF?

	▶ Fault is intermittent caused by poor connection in circuit. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
	▶ In case of circuit error, go to next step. ▶ In case of pressure sensor falut , replace HECU by referring to shop manual.