DIY steering wheel sensor repair

In detail: DIY repair of the steering wheel rotation sensor from a real master for the site my.housecope.com.

Start with the fact that
find out where this steering wheel sensor is located and what it is for
used. As well as the principle of its operation, what consequences may arise,
if it breaks down and possible actions when repairing it.

The steering wheel sensor is located under the return and slip rings
airbags and this device is installed on the steering column, in
the middle between the switches and the steering wheel.

Why is it needed?

Angle sensor
steering wheel rotation is necessary in order to determine the steering angle or relative steering angle, as well as the direction of rotation, the required angle
and the angular velocity, steering wheel. The functions are determined by the required systems in your vehicle.

So, summing up,
it is safe to say that this sensor determines the direction of
the movement that the driver asked him.

Regarding principles
work, then you can list its main details, namely: encoding
disc with a pair of rings and photovoltaic pairs, which are
separately have a light source and a photocell itself.

As it was already above
it is said that the coding disc has two rings, namely an outer and an inner one.
The outer ring is needed to detect corner turns or, to put it another way,
the absolute values ​​of the steering wheel angle. The inner ring is required for
detecting the increments of this angle. The increment ring is divided into five sections, each with a degree of 72. This ring
interacts with one of the photovoltaic pairs. For each section, a ring
has a number of cuts and their order in relation to one
section remains unchanged, and in some individual sections this number
is different. That is why the coding of these sections is carried out. What's this
touched the inner ring.

Video (click to play).

The outer ring is necessary for determining the absolute values ​​or turns of the steering angle.
wheels. The outer ring works by interacting with six photovoltaic
in pairs. And by the way, the steering wheel rotation sensor is capable of
count down to 1044 degrees. And the direct reading is calculated by
addition of numbers of degrees that go over the mark in 360 degrees and the sensor
the steering wheel locks the end of the turn by one full turn.

With regard to measurements
angle, then here we can say that this procedure is performed due to
signals from a photoelectric sensor, which works in conjunction with a movable
screen. The principle of operation is that a beam of light passes through
a special cutout on the ring and on the terminals of the photocell voltage appears. AND
if this beam is interrupted, then the voltage will disappear. In general, with
displacements of the ring, a regular sequence of impulses appears. AND
the same sequence of voltage pulses appears on each of the
photovoltaic pairs that interact with the ring
absolute values. And all this nascent sequence goes to the block
boards, and there they are processed using electronic devices that are available
on the steering column.

What happens if the steering wheel sensor comes out of
building?

If the sensor, suddenly
turns out to be faulty, then, as a rule, the backup function is connected, thanks to
which, instead of the alternating signal of this sensor, is connected to the control
constant signal. With this action, the amplifiers remain completely
safe. As for the malfunction itself, the flash will tell about it
control lamp.

Angle sensors
steering wheel are of three types, namely potentiometric, optical and
magnetoresistive.

As for the first one,
then it can be attributed to contact sensors. It has two potentiometers which
attached to the steering column, one of these potentiometers is offset from the
to the other by 90 degrees and this allows you to determine the relative and absolute
steering wheel angles. Sensors of this type are now practically not
are used, due to the low reliability caused by the presence of moving contacts.

The second sensor is optical, it combines the coding disk, light sources and
photosensitive elements, as well as the block itself, which determines the number of full
revolutions during rotation. This type of sensor is the most advanced.

And the last third - a magnetoresistive steering wheel angle sensor - this is even more
universal device. Because this sensor, in addition to the relative and
the absolute angle of rotation of the steering wheel, it can also calculate its angular velocity. If you delve into it
constructiveness, then it can be revealed that this sensor includes two
magnetoresistive elements that are attached to the sensor body and they
work in conjunction with a pair of moving magnets. This
the sensor has magnetoresistors, and each magnet performs rotational
movement by means of a gear transmission. And the drive gears have
different number of teeth. And measurement data has for each location
the steering wheel has its own arrangement of magnets that are fixed
magnetoresistors. And therefore the control unit itself is able to determine the value
cornering angles, as well as their direction and speed.

You are kindly requested, before asking a question in the config and opening a new topic, look for the answer to your question here:
LINK 1, here: LINK 2 and here: LINK 3
I am sure that 90% of the answers you will find on the links provided. Also - try searching from the MAIN page of the site - there may be more complete results!

P.S If you know the error code, then just type it into the search line. And note that the first letter of the code must be typed in the "Latin" layout! Otherwise, the search results will lead you nowhere.
The first letter of the code is NOT the Russian letter “P”!

And yet - a HUGE request to write in this forum in RUSSIAN - save Albanian for a smoking room.

Newbie
Image - DIY steering wheel turn sensor repair