Steering is installed on cars with a gear-rail steering mechanism equipped with an electric amplifier and an injury-proof steering column adjustable in angle of inclination and departure

The steering drive consists of two steering rods and two of their tips connected by ball joints with the levers of the rotary fists of the front suspension.

The control device in the electric power steering system is the electronic control unit of the electric power steering system (EPS)

Based on the information received from the sensors mounted on the steering column and the electronic control units of the engine and the ABS system, the control unit of the electric power steering system includes a motor reducer on the steering mechanism to obtain additional torque

The electric power steering system, along with the electronic control unit, includes sensors, actuators, connectors and fuses.

The electronic control unit (ECU) of the electric power steering system (EPS) is installed in the engine compartment under the main brake cylinder

The electronic control unit is connected by electrical wires to all sensors of the system

Mazda car steering design 6

The electric power steering control unit determines the direction and value of the additional force depending on the vehicle speed and signals from the torque sensor mounted on the steering column shaft

As a result, the ECU of the electric booster system adjusts the steering wheel force depending on the speed of the car: the lower the speed of the car, the greater the force; on the contrary, at high speed, the steering wheel force is minimal

This characteristic of the operation of the electric booster provides ease of maneuvering when driving at low speed and a sense of feedback on the steering wheel when driving at relatively high speeds.

The rotor speed sensor is mounted on the steering gear housing

Mazda car steering design 6

The sensor determines the value of the torsion shaft twist angle and converts it into an electrical signal entering the ECU of the electric booster system

The torque sensor is mounted on the shank of the steering shaft gear

Mazda car steering design 6

The sensor converts the steering angle value into an electrical signal received by the ECU of the electric power steering system.

The steering angle sensor is mounted on the steering column between the steering wheel switches and the steering wheel (under the return and sliding rings of the airbag)

Mazda car steering design 6

The electronic engine control unit installed in the engine compartment transmits data on the engine crankshaft rotation speed to the ECU of the electric power steering system.

The ABS hydroelectronic module located in the engine compartment transmits data on the speed of the car to the control unit of the electric power steering system.

Mazda car steering design 6

The electric power steering motor creates an additional twistingthe moment when the voltage is applied to it by the signals of the control unit of the electric amplifier system.

Steering wheel with driver"s airbag

Mazda car steering design 6

An audio signal switch is installed in the central steering wheel cover

The steering wheel hub is bolted to the steering column shaft.

The steering mechanism is installed in the engine compartment and secured with three bolts on the front suspension subframe.

Mazda car steering design 6

The steering rods are attached to the rack of the steering mechanism 7 (see Fig. 7) by ball joints

Mazda car steering design 6

The tips of the steering rods 2 with ball joints 1 are attached to the rotary fists of the front suspension

From turning on the steering rods, the tips are fixed with lock nuts 3. By rotating the steering rod in the ball joint relative to the tip, the convergence of the front wheels is regulated.

Mazda car steering design 6

The steering column is injury-proof, with a mechanism 6 (Fig. 9) for adjusting the position of the steering wheel, equipped with energy-absorbing devices (intermediate shaft) 2, increasing passive safety, and an anti-theft device in the ignition lock 7, blocking the steering wheel shaft from turning.

Checking the steering on the car

Check the steering condition regularly, as the safety of driving depends on it.

When inspecting the steering, pay special attention to the condition of the protective covers and threaded connections. Torn, cracked or elastic rubber covers must be replaced, otherwise water, dust and dirt trapped in the nodes will quickly disable them.

Check the location of the steering wheel spokes, which, when the front wheels are in a straight line, should be positioned symmetrically relative to the vertical axis

Otherwise, determine the cause of the malfunction and fix it.

Turning the steering wheel from stop to stop, check visually and by ear:

- reliability of the steering mechanism and steering wheel attachment;

- no gap in the steering rod bushings and ball joints of the steering rod tips;

- reliability of tightening and locking of bolts of fastening of rods to the rail and nuts of fingers of ball joints;

- no jamming and interference that prevents the steering wheel from turning.

If you find knocks and jams, disconnect the steering rods from the rotary levers of the shock struts and repeat the check. If the knocking and jamming does not stop, remove the steering mechanism from the car and repair it.

Checking the steering on a Mazda 6

Check the condition of the protective covers of the steering rod tips. Replace torn, cracked or loose covers.

Turning the steering wheel sharply in both directions (an assistant should do this), visually and audibly check the fastening of the steering mechanism. Movement of the mechanism and knocking are not allowed.

Checking the steering on a Mazda 6

Check for backlash in the ball joints of the steering rod tips. Replace the tips whose hinges have a noticeable backlash

Also check the reliability of tightening the nuts of the fingers of the ball joints of the tips of the steering rods

Checking the steering on a Mazda 6

Check the condition of the steering rod protective covers. Be sure to replace the damaged covers.

Checking the free running (backlash) of the steering wheel

With increased free travel of the steering wheel, it is difficult to control the car, since it reacts late to the actions of the driver

In addition, the increased stroke, which cannot be eliminated by adjusting the steering mechanism, indicates a malfunction of the steering control (loosening of the fastening of the steering mechanism, steering rods or wear of their parts).

Check the steering wheel backlash on a car mounted on a flat non-slip surface. The backlash should not exceed 5 °. The backlash can also be determined in linear units (mm) by the formula L = (5º/360º )πD, where L is the steering wheel backlash, mm; π = 3.14; D is the outer diameter of the steering wheel, mm.

For example, for a steering wheel with an outer diameter of 370 mm, the backlash should not be more than 14-16 mm.

You will need: a ruler (rail), chalk or wire (insulating tape) for marking, a caliper.

Set the front wheels to the position corresponding to the rectilinear movement of the car.

Checking the steering on a Mazda 6Checking the steering on a Mazda 6

Install the ruler (rail) so that its end rests against the instrument panel, and the plane of the ruler touches the outer surface of the steering wheel rim.

Without changing the position of the ruler, turn the steering wheel to the left until the front wheels start turning. In this position, mark the steering wheel rim (secure the wire or insulation tape).

Checking the steering on a Mazda 6Checking the steering on a Mazda 6

Without changing the position of the ruler, turn the steering wheel to the right until the front wheels start turning. In this position, apply a second mark to the steering wheel rim (secure the wire or insulation tape).

Measure the distance between the marks along the rim. It should be no more than the calculated value. If the distance (free running of the steering wheel) is greater, it is necessary to establish the cause and eliminate it.

Possible steering malfunctions and solutions

Increased steering wheel freewheel

- loosening of nuts of fastening of ball pins of rods

Tighten the nuts

- increased clearance in the ball joints of the rods

Replace the rod tips

- increased gap between the rail stop and the nut

Replace worn parts and adjust steering gear

Noise (knocking) in the steering

- loosening of nuts of ball joints of rods

Check and tighten the nuts

- increased gap between the rail stop and the nut

Replace worn parts and adjust steering gear

- loosening of the steering mechanism attachment

Tighten the steering gear nuts

Tight steering wheel rotation

- damage to the bearing of the upper support of the suspension strut

Replace the bearing or support assembly

- damage to the support sleeve or rail stop

Replace damaged parts, apply grease

- low tire pressure of the front wheels

Set normal tire pressure

- damage to the parts of the ball joints of the rods

Replace damaged parts

- the electric power steering is faulty

Replace the electric booster assembly with the steering column