ELECTRIC PARKING BRAKE SWITCH INDICATOR LIGHT IS ON OR OFF CONSTANTLY [ELECTRIC PARKING BRAKE]

id040328250400

Troubleshooting item	Electric parking brake switch indicator light is on or off constantly
Description	•  Electric parking brake switch indicator light is on constantly. •  Electric parking brake switch indicator light is off constantly.
Possible cause	•  Electric parking brake switch connector or terminal malfunction •  Short to ground or open circuit in electric parking brake switch indicator light power supply circuit •  Electric parking brake switch malfunction •  Electronically controlled brake unit connector or terminal malfunction •  Short to ground or open circuit in electric parking brake switch indicator light control circuit •  Electronically controlled brake unit malfunction

Diagnostic Procedure

Step	Inspection	Results	Action
1	VERIFY ALL SYSTEM DTCs •  Switch the ignition off. •  Switch the ignition ON (engine off or on) and wait for 10 s or more. •  Perform the Quick Check using the M-MDS. (See DTC INSPECTION.) •  Are any DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)
		No	Go to the next step.
2	VERIFY IF THE ELECTRIC PARKING BRAKE WARNING LIGHT IS TURNED ON •  Verify if the electric parking brake warning light is turned on. •  Is the electric parking brake warning light turned on?	Yes	Perform an inspection referring to “ELECTRIC PARKING BRAKE WARNING LIGHT TURNS ON”. (See ELECTRIC PARKING BRAKE WARNING LIGHT TURNS ON [ELECTRIC PARKING BRAKE].)
		No	Go to the next step.
3	INSPECT ELECTRIC PARKING BRAKE SWITCH CONNECTOR CONDITION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  Are the connector and terminal normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT ELECTRIC PARKING BRAKE SWITCH INDICATOR LIGHT POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT •  Inspect the power supply circuit for an open circuit and short to ground. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location, and perform the repair completion verification.
5	INSPECT ELECTRIC PARKING BRAKE SWITCH •  Inspect the applicable part. (See ELECTRIC PARKING BRAKE SWITCH INSPECTION.) •  Is the part normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See ELECTRIC PARKING BRAKE SWITCH REMOVAL/INSTALLATION.)
6	INSPECT ELECTRONICALLY CONTROLLED BRAKE UNIT CONNECTOR CONDITION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  Are the connector and terminal normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT ELECTRIC PARKING BRAKE SWITCH INDICATOR LIGHT CONTROL CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT •  Inspect the control circuit for an open circuit and short to ground. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Replace the electronically controlled brake unit, and perform the repair completion verification. (See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION.)
		No	Repair or replace the malfunctioning location, and perform the repair completion verification.
Repair completion verification	VERIFY THAT MALFUNCTION SYMPTOMS DO NOT RECUR AFTER REPAIR •  Install/connect the part removed/disconnected during the troubleshooting procedure. •  Has the malfunction symptom been eliminated?	Yes	Complete the symptom troubleshooting. Explain to the customer what has been repaired.
		No	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW.) If the CAN communication is normal, perform the diagnosis from Step 1.