6.6. The traction control system (TCS) - the description and replacement of components

Description

The TCS system is installed on early models as the additional equipment, and as the standard equipment on late models, high-class. The traction control system (TCS) serves for prevention of pro-slipping of wheels at acceleration on slippery surfaces. The TCS system works together with system of anti-blocking of brakes (ABS) (see the Head the Brake system). The main components of the TCS system is the following:

   a) Electronic control by a throttle (ETS):

The TCS system in addition to trosikovy control of the throttle gate on the throttle case, uses electronic control (ETS). The ETS system includes a potentiometer of a pedal and a throttle potentiometer / motor. When squeezing by the driver of a pedal of an accelerator, at the included system, the potentiometer gives a signal to the electronic module of management of the ETS system. In normal conditions the module of management turns on the motor of a throttle and installs the throttle gate in direct dependence on the provision of a pedal. At emergence of pro-slipping of wheels at the set speed of the movement the module of management defines on how many it is necessary to cover the gate for reduction of torque of the engine for the purpose of restoration of coupling of wheels with the road. Change of provision of a throttle is usually applied only at speeds over about 50 km/h. The throttle potentiometer informs the module of management on position of the gate of a throttle.

   b) Module of management of the ETS system:

The module of management of the ETS system is located on a bracket under the left front seat, and on models with automatic transmission the module of the ASR traction control system is fixed from above on the module of management of the ETS system. On models with the manual transmission the module of the traction control system is built in the control unit of system of anti-blocking of brakes (ABS). The module of management of the ETS system obtains information from the TCS/ABS control unit (antiprobuksovochny system / anti-blocking system of brakes) (the manual transmission) or the ASR module (traction control system) on models with automatic transmission, and on the basis of the obtained information defines the moment of the beginning of pro-slipping of wheels.

   c) Hydraulic activator of the TCS/ABS system (traction control system / anti-blocking system of brakes):

Hydraulic activator of the TCS/ABS system
(traction control system / anti-blocking system of brakes)


The hydraulic activator of the TCS/ABS system consists of the block which is turning on electromagnetic valves and the pump, built in a hydraulic contour of forward brakes. The system uses sensors of wheels of system of anti-blocking of brakes of ABS for definition of the moment of pro-slipping of wheels via the control unit of the ABS system installed on the battery pallet. On the models equipped with the TCS system the special control unit of system of anti-blocking of brakes (ABS) which gives a signal for the module of management of the ETS system (electronic control by a throttle) at detection of the moment of pro-slipping of wheels is installed. At speeds of movement lower than 50 km/h the activator of electromagnetic valves turns on that allows the pump to lift pressure in the corresponding contour of forward brakes with the purpose to reduce the speed of rotation of the slipping wheel to the value necessary at this speed of the car. The effect is similar to effect of transfer of the rotary moment to a wheel with normal coupling with the road.

   d) System switches:

Pressure switch in the activator of the TCS system turns on with a pressure of 6.0 bars, at the same time the alarm lamp on an instrument guard informing the driver that the TCS system is included lights up and suppresses pro-slipping of a wheel. In case of malfunction of system joins and continuously the alarm lamp with the designation "TCS CTRL" burns. In case the TCS system is involved for a long time, the alarm lamp of TCS CTRL begins to blink that informs the driver that the TCS system is temporarily disconnected in order to avoid an overheat of brakes.

   e) Main control switch:

The main control switch is located on the forward panel ("Torpedo").

In case of malfunction of the traction control system first of all it is necessary to check reliability of fastening of wires. At emergence of malfunction ways, by full pressing of a pedal of an accelerator and the subsequent its otpuskaniye can include the limited mode. In this mode the throttle copes a rope. In the limited mode engine capacity is limited, the pedal of an accelerator is rigidly established, and systems of a tempostat and air conditioning are disconnected. Further checks of system have to be made in representative office of SAAB having the corresponding diagnostic equipment for bystry search of the reasons of malfunctions. The system is not subject to adjustment.

Replacement of components

Accelerator pedal potentiometer

ETS system accelerator pedal potentiometer (electronic control by a throttle)


 PERFORMANCE ORDER

1. Working in the car, disconnect the plug from a potentiometer.
2. Disconnect the potentiometer lever from an accelerator pedal.
3. Otboltite also remove the block.

Installation in an order the return to a removal order.

Throttle potentiometer / motor

Throttle potentiometer / motor of the ETS system (electronic control by a throttle)


 PERFORMANCE ORDER

1. Disconnect the plug from the throttle potentiometer / motor.
2. Disconnect the throttle lever.
3. Otboltite also remove the block.

Installation in an order the return to a removal order.

Module of management of the TCS system (electronic control by a throttle)

In case the new module of management is installed, you remember that before connecting the plug, the module has to be programmed (on manual or automatic transmission) by representative office of SAAB (new modules are delivered not programmed). Also you remember that the module is very sensitive to influence of static electricity (it is made on technology KMOP), and during the work with the module it is necessary to samozazemlitsya.


 PERFORMANCE ORDER

1. Shift, it is as much as possible forward, the left front seat.
2. Lift a rug, then an otboltita and uncover.
3. Disconnect the plug and take out the module of management from interior of the car. On models with automatic transmission remove the ASR module (antiprobuksovochny) from the top part of the module of management of ETS (system of electronic control by a throttle).

Installation in an order, the return to a removal order.

Alarm lamp

 PERFORMANCE ORDER

1. Remove the control panel of system of automatic control of climate (see the Head of the Cooling system, heating).
2. Take out an alarm lamp and disconnect the plug.

Installation in an order, the return to a removal order.