Code No. P0703: Malfunction of Stop Lamp Switch

DIAGNOSTIC FUNCTION

CVT-ECU detects malfunction using the stop lamp switch signal sent from the ETACS-ECU.

JUDGEMENT CRITERIA

Drive the vehicle at 30 km/h or more for 10 seconds, and then turn the ignition switch to the OFF position. In this sequential operation, no variation has been found in the stop lamp switch input signal in two consecutive times.

PROBABLE CAUSES

Malfunction of CAN bus line
Malfunction of the stop lamp switch
Damaged wiring harness and connectors
Malfunction of CVT-ECU
Malfunction of ETACS-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics

Use M.U.T.-III to perform the CAN bus diagnosis.

Q. Is the check result normal?

	Go to Step 2

	Repair the CAN bus lines.

STEP 2. M.U.T.-III data list

Item 59: Brake switch

OK: The service data changes in response to the brake operation.

Q. Is the check result normal?

	Go to Step 3

	Check the stop lamp switch circuit. (Refer to GROUP 54A - ETACS, Trouble Symptom Chart for Input Signal ).

STEP 3. Symptom recheck after erasing diagnosis code

Q. Is the diagnosis code set?

	Replace CVT-ECU.

	Intermittent malfunction.