Mazda Training manual — part 96

Dynamic Driving Safety Systems

TCS

TCS Indicator Light

•

The yellow TCS indicator light is located in the IC. It illuminates after ignition on for a few
seconds to inform the driver that the warning light has no malfunction. During driving it
flashes whenever TCS operates, to visually inform the driver that the system is currently
operating.

•

If it stays on or illuminates without flashing during driving, a malfunction is detected. An
illuminated indicator light, does not necessarily indicate that the system is disabled. It
only indicates, that the driver should have the system inspected as soon as possible. All
current Mazda vehicles feature a DTC memory function. The malfunction is stored in the
ABS CM.

L2003_02024

1

IC

2

TCS indicator light

Diagnostics

•

The TCS indicator light can be checked by:

–

Visually inspecting the light after switching the ignition on

–

Using the input/output check mode for the IC

Curriculum Training

02-43

TCS

Dynamic Driving Safety Systems

TCS OFF Indicator Light

•

The yellow TCS OFF indicator light is located in the IC. It illuminates after ignition on for
a few seconds to inform the driver that the indicator light has no malfunction. It is also
illuminated when the TCS is switched off by the driver, or if the TCS is disabled due to a
malfunction.

•

If it illuminates without the TCS having been switched off by the driver, a malfunction is
detected. All current Mazda vehicles feature a DTC memory function. The malfunction is
stored in the ABS control module.

NOTE: On vehicles without electronic throttle valve, the TCS OFF indicator light might stay

illuminated after the engine has been started at an engine coolant temperature below
0° C. Because, the system is automatically disabled until the engine coolant
temperature reaches a specified value (depending on the model approx. 35° C), to
avoid engine running problems caused by changing the ignition timing of the cold
engine. This does not indicate a malfunction.

L2003_02025

1

IC

2

TCS OFF indicator light

Diagnostics

•

The TCS OFF indicator light can be checked by:

–

Visually inspecting the light after switching the ignition on

–

Using the input/output check mode for the IC

02-44 Curriculum

Training

Dynamic Driving Safety Systems

TCS

TCS OFF Switch

•

The TCS OFF switch is located in the dashboard. With this momentary switch, the driver
can disable the TCS operation in case the vehicle is stuck and spinning the wheels may
help to free the vehicle.

•

Whenever the TCS is switched off, the TCS OFF indicator light will be illuminated in the
IC. The TCS will automatically be switched on again, after switching the ignition off and
on.

L2003_02026

1 TCS

OFF

switch

Diagnostics

•

The TCS OFF switch can be checked by:

–

Visually inspecting the TCS OFF indicator light while switching the TCS on and off

–

Measuring voltage signals and resistance

Curriculum Training

02-45

DSC

Dynamic Driving Safety Systems

TCS on Vehicles with 4WD

•

The system is similar to that on a 2WD vehicle, except that a torque request signal can
be transmitted to the 4WD CM

•

When the TCS CM detects a condition where it is necessary to increase the torque
transmitted to the rear wheels, it transmits a torque request signal via CAN to the 4WD
CM. Based on this request signal, the 4WD CM activates the electronically controlled
clutch to increase the torque forwarded from the propeller shaft to the rear differential
and on to the rear wheels.

NOTE: Due to the fact that the TCS on vehicles with 4WD is similar to that on vehicles with

2WD, the system can be inspected in the same way.

Dynamic Stability Control

•

The DSC (Dynamic Stability Control) system is designed to increase the vehicle’s driving
stability, especially if the vehicle tends to understeer/oversteer, e.g. when cornering too
fast.

•

The DSC detects tendency for swerving with the aid of its input signals, and reduces this
by applying a calculated amount of brake force to a single wheel and/or by controlling
the engine torque (similar to TCS control).

•

The DSC is incorporated into the ABS HU/CM. The module is called a DSC HU/CM. The
DSC features the following changes in components over an ABS with TCS:

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Two stability control solenoid valves are added

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A combined sensor is added

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A steering angle sensor is added

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A brake fluid pressure sensor is either attached to the brake master cylinder or
integrated to the HU

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A DSC indicator light and a DSC OFF indicator light are added to the IC

–

A DSC OFF switch is added to the dashboard

–

The vehicle has neither a TCS OFF indicator light nor a TCS OFF switch

NOTE: Because a large number of components is similar to those of an ABS with TCS, only

the differences are explained.

02-46 Curriculum

Training