PRECAUTION [DYNAMIC STABILITY CONTROL (DSC)]

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1.  The ABS warning light and/or brake system warning light and/or TCS/DSC indicator light and/or DSC OFF indicator light illuminate even when the system is normal.

Warning lights/Indicator 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 and DSC control
•  ABS warning light •  Brake system warning light •  TCS/DSC indicator light	Only the front wheels rotate under the following condition while jacked up, stuck, or on the chassis dynamometer: •  Detected one time for a continuous 10 s while at a vehicle speed of 20 km/h {12 mph} or more. (One detection period is when ignition is switched from ON to off.)	After turning off the ignition once and then restarting the engine, the vehicle is driven at 10 km/h {6.2 mph} or more, and then normal operation is verified.	•  ABS: Cuts control. •  EBD: Cuts control. ―  Control disabled •  Wheel speed sensor malfunction in two wheels or more is detected ―  Control enabled •  Wheel speed sensors in three wheels or more are normal •  TCS: Cuts control. •  DSC: Cuts control.
	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.)
	Battery voltage at DSC HU/CM terminal of voltage source drops below about 9 V.	Battery voltage rises above about 9 V.	•  ABS: Cuts control. •  EBD: Operates control. •  TCS: Cuts control. •  DSC: Cuts control.
Brake system warning light	Brake fluid amount is low.	Brake fluid level is with in the specification.	•  ABS: Operates control. •  EBD: Operates control. •  TCS: Operates control. •  DSC: Operates control.

2.  Precautions during servicing of DSC. The DSC is composed of electrical and mechanical parts. It is necessary to categorize malfunctions as being either electrical or hydraulic when performing troubleshooting.

(1)  Malfunction in electrical system

•  The control module has an on-board diagnostic function. With this function, the ABS warning light and/or brake system warning light and/or TCS/DSC indicator light and/or DSC OFF indicator light will come on when there is a problem in the electrical system.

Also, past and present malfunctions are recorded in the control module. This function can find malfunction that do not occur during periodic inspections. Connect the M-MDS to the DLC-2. The stored malfunctions will be displayed in the order of occurrence. To find out the causes of DSC malfunction, 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 control module usually operates normally. Be careful when searching for the cause of malfunction.

•  After repair, it is necessary to clear the DTC from the control module memory. Also, if the DSC 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 control module, the ABS warning light may not go off even when the ignition is switched to ON. In this case, drive the vehicle at a speed of more than 10 km/h {6.2 mph}, make sure the ABS warning light goes off, and then clear the DTC.

•  When repairing, if the DSC related connectors are disconnected and the ignition is switched to ON, the control module will mistakenly detect a fault and record it as a malfunction.

Caution

•  When any DSC HU/CM (brake fluid pressure sensor), SAS control module (yaw rate sensor, low-G sensor) are replaced. Perform the sensor standard point installation of each sensor.

•  To protect the control module, make sure the ignition is off before connecting or disconnecting the control module 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 a DSC component or the conventional brake system.

•  The hydraulic unit contains delicate mechanical parts. If foreign materials get into the component, the DSC 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 DSC does not. Make sure foreign materials do not get inside when servicing the DSC (e.g. brake fluid replacement, pipe removal).

3.  Clunk / bang / buzz noise during first forward movement after sitting

•  A slight clunk/bang/buzz noise or jolt from the front of the vehicle is considered normal if it occurs during the vehicle's first forward movement after starting the engine. This is a normal operating noise of the dynamic stability control (DSC). Do not attempt any repairs.

•  If a customer complains about this, explain that the noise comes from the ABS/TCS/DSC “Malfunction Detection Function” initial check and that there is no problem.

•  This initial check is a necessary function to ensure the normal operation of the ABS/TCS/DSC system. It occurs when the vehicles first moves forward under the following conditions.