Modulator

Consists of the electric pump and four electromagnetic valves. The electric pump creates pressure and fills tanks in the modulator. The pump and tanks are placed in the modulator block. Electromagnetic valves modulate pressure in wheel brake cylinders at ABS work.

Sensors of frequency of rotation

Are located about each wheel. They develop impulses when about them pass teeths of rotors, and transfer them to the electronic control ABS device on the basis of what frequency of rotation of wheels is calculated.

Fig. 11.3. Forward sensor of frequency of rotation: 1–rotor of the sensor of frequency of rotation of a forward wheel; 2–plug; 3–sensor of frequency of rotation of a forward wheel

Forward sensors of frequency of rotation are established on rotary fists in close proximity to a rotor which (fig. 11.3) is an integral part of the external CV JOINT of a shaft of a drive of a wheel .

Fig. 11.4. The back sensor of frequency of rotation on all models till 2001 and on all-wheel drive models since 2001: 1–sensor of frequency of rotation of a back wheel; 2–rotor of the sensor of frequency of rotation of a back wheel

Fig. 11.5. The back sensor of frequency of rotation on models with one leading bridge of release since 2001: 1–electric socket; 2–sensor of frequency of rotation of a back wheel; 3–nave; 4–brake drum

On all models till 2001 and on all-wheel drive models since 2001 back sensors of frequency of rotation fasten bolts to levers of a back suspension bracket (fig. 11.4) . On models with one leading bridge since 2001 to the central part of a back nave (fig. 11.5) .

Delay sensor

It was established on all-wheel drive models till 2001 and all models since 2001. The sensor is established under the central console and transmits signals about negative accelerations to the electronic control ABS device.

On models till 2001 it is located under the dashboard from the forward passenger, and on models since 2001 it is incorporated with the modulator block. EBU function — to accept and process information received from sensors of frequency of rotation of wheels, and to operate pressure in the pipeline so that to exclude blocking of wheels. The electronic control unit carries out also diagnostic function, fire of a control lamp warning the driver about failure detection in electric chains or the elements ABS. The code of malfunction is brought in memory of EBU and can be read without use of special devices.

Before a call of codes of malfunctions execute some simple checks:

– check level of brake liquid in a compensatory tank;

– check reliability connection of all electric ABS sockets;

– check integrity of safety locks.

The electronic control unit stores a malfunction code while his memory will not be cleared, or malfunction will not be eliminated.

The control lamp of ABS should light up after inclusion of ignition and go out at once after engine start-up. If the lamp continues to burn, the system of self-diagnostics registered malfunction in electric chains or elements of anti-blocking system.

Fig. 11.6. An arrangement of a crossing point (1) in the diagnostic socket on models till 2001

Fig. 11.7. An arrangement of contacts of Tc and E1 of the diagnostic socket on models till 2001

Fig. 11.8. An arrangement of the diagnostic socket and E1 and CG contacts on models since 2001

To read diagnostic codes of malfunction it is possible as follows. Turn the ignition key in the situation OFF (ignition is switched off). On models till 2001 remove a crossing point 1 (fig. 11.6) , then an additional wire connect contacts of Tc and E1 of the diagnostic socket located about a compensatory tank of the amplifier of a steering (fig. 11.7) . On models since 2001 connect contacts of E1 and CG of the diagnostic socket located on the left side under the dashboard (fig. 11.8) . Include ignition, without getting the engine, and by number of flashes of a control lamp of ABS determine a malfunction code.

Number of a diagnostic code is determined by number of flashes of a control lamp of ABS. In the presence of malfunction of flash of a control lamp of ABS occur in two series the interval between which makes 1,5 pages. For example, a code 34 (malfunction in a chain of the sensor of frequency of rotation of a back left wheel): the lamp flashes 3 times, a pause 1,5 with, then the lamp flashes 4 more times. If in memory some codes of malfunctions are brought, before indication of each subsequent code the pause makes 2,5 pages. In the absence of malfunctions the control lamp flashes each 0,5 pages.

Diagnostic codes, the reasons and methods of elimination of malfunctions are given in tab. 11.3 .

After reading of codes and elimination of malfunctions clear memory of EBU. On models till 2001 separate contacts of E1 and Tc of the diagnostic socket, and on models since 2001 separate E1 and CG contacts. Include ignition, without getting the engine, and clear memory of EBU, having pressed a pedal of a brake of 8 or more times during 3 pages. On models till 2001 establish into place a crossing point 1 (fig. 11.6) . Close a cover of the diagnostic socket.

Check of an electric food and connection with "weight"

Fig. 11.9. Electric sockets (And and In) the dual relay

All checks of an electric food and connection with "weight" make with tester use, connecting it to contacts previously the disconnected electric socket of the dual relay (fig. 11.9) .

Tests of check of an electric food and connection with "weight" are provided in tab. 11.4 .

Check of sensors of frequency of rotation of wheels

Check of sensors of frequency of rotation of wheels make at the electric sockets disconnected from the control unit. The procedure for test is given in tab. 11.5.