3

Brake system warning lights remains illuminated

POSSIBLE CAUSE

• Brake fluid amount is low.

• Parking brake does not release.

• Parking brake switch or brake fluid level sensor stuck on.

• Short to ground in following circuit:

• Between parking brake switch and instrument cluster

• Between brake fluid level sensor and front body control module (FBCM)

• No connection at DSC HU/CM connector (When DSC HU/CM connector is removed, ABS warning light, brake system warning light, TCS/DSC indicator light, and TCS OFF indicator light are illuminated.)

• DSC HU/CM detected malfunction. (Input and output device malfunction)

• DSC HU/CM detects low voltage in power supply.

• DSC HU/CM ground malfunction (When DSC HU/CM ground is not securely connected, ABS warning light, brake system warning light, TCS/DSC indicator light, and TCS OFF indicator light are illuminated but DTCs are not display.)

• DSC HU/CM does not operate.

• Front body control module (FBCM) detected malfunction.

• DSC HU/CM internal malfunction

• Instrument cluster detected malfunction

STEP

INSPECTION

ACTION

1

• Inspect the brake fluid amount and verify that the parking brake is released.

• Is the brake fluid amount normal?

• Is the parking brake lever released?

Yes

Go to the next step.

No

Add the brake fluid or release the parking brake lever.

If the brake fluid amount is less than specification:

• Inspect and repair the brake line for leakage.

2

• Retrieve the DSC HU/CM DTC using the M-MDS (IDS).

  (See ON-BOARD DIAGNOSIS [DYNAMIC STABILITY CONTROL (DSC)].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See ON-BOARD DIAGNOSIS [DYNAMIC STABILITY CONTROL (DSC)].)

No

If a communication error message is displayed on the M-MDS (IDS) screen:

• Go to the next step.

If a communication error message is not displayed:

• Go to Step 4.

3

• Inspect the connection of the DSC HU/CM connector.

• Is the DSC HU/CM connector connected securely?

Yes

Go to the next step.

No

Connect the DSC HU/CM connector securely, then go to the next step.

4

• Retrieve the warning system operation history using the M-MDS (IDS).

  (See INSTRUMENT CLUSTER OPERATION RECORD.)

• Is the brake system warning light illumination history recorded?

Yes

If the Brake Warning Lamp is recorded:

• Go to Step 5.

If the Brake Warning Lamp (Brake fluid low) is recorded:

• Go to Step 6.

If the Brake Warning Lamp (Parking Brake ON over 20 km/h or 12.4 mile/h) is recorded:

• Go to Step 8.

No

Go to Step 10.

5

• Connect the M-MDS (IDS) to the DLC-2.

• Turn off and on all warning lights and indicator lights using the instrument cluster PID WL+IL of active command modes.

  (See ACTIVE COMMAND MODES INSPECTION [INSTRUMENT CLUSTER].)

• Do the ABS warning light, brake system warning light, TCS/DSC indicator light and DSC OFF indicator light turn on and off according to the active command modes?

Yes

Go to Step 10.

No

Replace the instrument cluster.

(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)

6

• Inspect the brake fluid level sensor for continuity.

  (See BRAKE FLUID LEVEL SENSOR INSPECTION.)

• Is the continuity condition normal?

Yes

Go to the next step.

No

Replace the malfunctioning part.

(See MASTER CYLINDER REMOVAL/INSTALLATION.)

^*7

• Inspect for short to ground in the following circuit:

• Between brake fluid level switch and front body control module (FBCM) terminal 2Q

• Is a short to ground detected?

Yes

Repair or replace the wiring harness for a possible short to ground.

No

Retrieve the front body control module (FBCM) DTC using the M-MDS (IDS).

(See DTC INSPECTION [FRONT BODY CONTROL MODULE (FBCM)].)

If the DTC remains:

• Go to the applicable DTC inspection.

  (See DTC TABLE [FRONT BODY CONTROL MODULE (FBCM)].)

If the DTC does not remain:

• Replace the front body control module (FBCM).

  (See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION.)

8

• Inspect the following parts for continuity:

• Parking brake switch

  (See PARKING BRAKE SWITCH INSPECTION.)

• Is the continuity condition normal?

Yes

Go to the next step.

No

Replace the malfunctioning part.

(See PARKING BRAKE LEVER REMOVAL/INSTALLATION.)

^*9

• Inspect for short to ground in the following circuit:

• Between parking brake switch and instrument cluster terminal 2X

• Is the short to ground detected?

Yes

Repair or replace the wiring harness for a possible short to ground.

No

Retrieve the instrument cluster DTC using the M-MDS (IDS).

(See DTC INSPECTION [INSTRUMENT CLUSTER].)

If the DTC remains:

• Go to the applicable DTC inspection.

  (See DTC TABLE [INSTRUMENT CLUSTER].)

If the DTC does not remain:

• Replace the instrument cluster.

  (See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)

10

• Inspect the DSC HU/CM ignition power supply fuse.

• Is the fuse normal?

Yes

Go to the next step.

No

Inspect the blown fuse’s circuit for short to ground.

Repair or replace the wiring harness for a possible short to ground as necessary.

Install appropriate amperage fuse.

^*11

• Switch the ignition ON.

• Measure the voltage at the DSC HU/CM terminal Q (wiring harness-side).

• Is the voltage approx. 12 V?

Yes

Go to the next step.

No

Refer to the wiring diagram and verify whether or not there is a common connector between DSC HU/CM terminal Q (wiring harness-side) and ignition switch.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has an open circuit.

^*12

• Switch the ignition off.

• Disconnect the DSC HU/CM connector.

• Inspect for continuity between DSC HU/CM terminal AL (wiring harness-side) and body ground.

• Is there continuity?

Yes

Replace the DSC HU/CM. (open circuit in the DSC HU/CM)

(See DSC HU/CM REMOVAL/INSTALLATION.)

No

Repair or replace the wiring harness for a possible open circuit and poor contact in ground point.