Precaution [ABSH-Cs]: Notes

Any one or a combination of the ABS warning light, BRAKE system warning light, TCS indicator light, and TCS OFF light illuminate even when the system is normal.

PRECAUTION [ABSH-CS] CHART

Warning lights that may illuminate and/or flash

Cases in which the light may illuminate

Conditions in which the light will go out

ABS, EBD, TCS control

Any or all the following light (s) illuminate:

ABS warning light
BRAKE system warning light (⁽¹⁾)

Under any of the following conditions:

When the front wheels are jacked up, stuck, or placed on a chassis roller, and only the front wheel ABS wheel speed sensors are spun for more than 60 s.

After turning ignition switch to OFF, vehicle is driven at speed greater than 10 km/h {6.2 mph} and normal operation is confirmed.

ABS: Cuts control.
EBD:
1. Cuts control, in cases where the light may illuminate, only when ABS/TCS HU/CM detects that a wheel speed sensor determines that more than the two rear wheels are malfunctioning.
2. Operates control, if wheel speed sensor determines that more than 3 wheels are functioning correctly.

Parking brake is not fully released while driving.

Brake drag.

Sudden acceleration/deceleration.

Left/right or front/rear tires are different. (Size, radius, tire pressure, or wear is other than that listed on tire label).

All the following lights illuminate:

ABS warning light
BRAKE system warning light

Battery voltage at ABS/TCS HU/CM ignition terminal Z drops below about 9 to 10 V. (⁽²⁾)

Battery voltage rises above about 10 V.
(Only BRAKE system warning light goes out).

ABS: Operates control.
EBD: Operates control.

⁽¹⁾	The light will illuminate only when ABS/TCS HU/CM detects that a rear wheel's speed sensor is malfunctioning.

⁽²⁾	If battery voltage drops below 9 V while vehicle speed is greater than 6 km/h {3.7 mph}, ABS/TCS HU/CM records DTC B1318.

PRECAUTION [ABSH-CS] CHART

Warning lights that may illuminate and/or flash

Cases in which the light may illuminate

Conditions in which the light will go out

ABS, EBD, TCS control

The following light illuminates:

TCS OFF light

When the engine coolant temperature is below 0°C {32°F}. (⁽¹⁾)

When engine is started and engine coolant temperature rises above 0°C {32°F}.

ABS: Cuts control.
EBD: Cuts control.
TCS:

If TCS is operating, cuts control after gradually released TCS control value.
If TCS is not operating, cuts control.

All the following lights flash:

ABS warning light
BRAKE system warning light
TCS OFF light

When confirming DTC, PID/DATA and ACTIVE COMMAND MODES item using the WDS or equivalent.

When ABS ON-BOARD DIAGNOSTIC SYSTEM is released.

ABS: Cuts control.
EBD: Cuts control.
TCS: Cuts control.

The following light illuminates:

TCS OFF light

For 1 s after starting the engine.

More than 1 s after starting the engine.

ABS: Cuts control.
EBD: Cuts control.
TCS: Cuts control.

Warning lights that may illuminate and/or flash.

Cases in which the light may illuminate.

Conditions in which the light will go out.

ABS, EBD, TCS control.

⁽¹⁾	DTC U2021 for past malfunction is not recorded in the ABS/TCS HU/CM. DTC U2021 for present malfunction displayed, but goes out when engine coolant temperature rises above 0°C {32°F}.

Precautions during servicing of ABS/TCS.
The ABS/TCS is composed of electrical and mechanical parts. It is necessary to categorize malfunctions as being either electrical or hydraulic when performing troubleshooting.
1. Malfunctions in electrical system
  - The ABS/TCS HU/CM has an on-board diagnostic function. With this function, any one or a combination of the ABS warning light, BRAKE system warning light, TCS indicator light, and TCS OFF light will come on when there is a problem in the electrical system. Also, past and present malfunctions are recorded in the ABS/TCS HU/CM. This function can find malfunctions that do not occur during periodic inspections. Connect the WDS or equivalent to the DLC-2. Stored malfunctions will be displayed in the order of occurrence. To find out the causes of ABS/TCS malfunctions, use these on-board diagnostic results.
  - If a malfunction occurred in the past but is now normal, the cause is likely a temporary poor connection of the harness. The ABS/TCS HU/CM usually operates normally. Be careful when searching for the cause of malfunction.
  - After repair, it is necessary to clear the DTC from the ABS/TCS HU/CM memory. Also, if the ABS/TCS related parts have been replaced, verify that the no DTC has been displayed after repairs.
  - After repairing the ABS wheel-speed sensor or ABS sensor rotor, or after replacing the ABS/TCS HU/CM, the ABS warning light may not go off (*) even when the ignition switch is turned ON. In this case, drive the vehicle at a speed of more than 10km/h {6.2mph}, make sure that ABS warning light goes off, and then clear the DTC.
    * The BRAKE system warning light also illuminates when there is any rear wheel deformations.
  - When repairing, if the ABS/TCS related connectors are disconnected and the ignition switch is turned ON, the ABS/TCS HU/CM will mistakenly detect a fault and record it as a malfunction.
  - To protect the ABS/TCS HU/CM, make sure the ignition is off before connecting or disconnecting the ABS/TCS HU/CM connector.
2. Malfunctions in hydraulic system
  - Symptoms in a hydraulic system malfunction are similar to those in a conventional brake malfunction. However, it is necessary to determine if the malfunction is in an ABS component or the conventional brake system.
  - The ABS hydraulic unit contains delicate mechanical parts. If foreign materials get into the component, the ABS may fail to operate. Also, it will likely become extremely difficult to find the location of the malfunction in the event that the brakes operate but the ABS does not. Make sure foreign materials do not get inside when servicing the ABS (e.g. brake fluid replacement, pipe removal).