Information sensors. BMW the 5th E28/E34 series (from 1981 to 1993 of release)
Repair of BMW E28 and series E34 from 1981 to 1993
1. Cars of the BMW brand of 5-series
2. Engine
3. Cooling system
4. Power supply system
5. Ignition system
6. Control systems of the engine and decrease in toxicity of the fulfilled gases
6.1. General information
6.2. General information about self-diagnostics of a control system by the Motronic engine
6.3. Removal and installation of the electronic control unit (ECU)
6.4. Information sensors
6.5. System of ventilation of a case (PCV)
6.6. Catching system паров gasoline (EVAP)
7. System of production of the fulfilled gases
8. Coupling
9. Manual box of gear shifting (RKPP) and automatic transmission (AT)
10. Transmission line
11. Steering and suspension bracket
12. Brake system
13. Body
14. Control body sizes
15. Heater and air conditioner
16. System of onboard electric equipment
17. Routine maintenance of the car
18. Size table and adjusting data
19. Schematic electric circuits
20. Governing bodies and operation receptions
21. System of onboard diagnostics - a principle of functioning and codes of malfunctions
 








6-4-informacionnye-datchiki.html

6.4. Information sensors

For additional information on an arrangement and diagnostics of the information sensors described in this Section, address to Heads the Power supply system and ignition System.

Sensor of temperature of a cooler

General description

The sensor of temperature of a cooler (it is shown by an arrow) is usually located near a temperature measuring instrument, near a regulator of pressure of fuel and represents a termistor (the resistor which resistance changes according to temperature). Change of resistance defines power failure on the sensor. At low temperatures resistance of the sensor the high. At temperature increase resistance falls. Refusals in a sensor chain in most cases occur because of weakening of contact of a wire or its short circuit; if problems with wires it is not observed, check the sensor as it is described below.

Check

 PERFORMANCE ORDER

  1. At sensor check, first of all measure its resistance in a cold condition (usually from 2100 to 2900 Ohm).
  1. Further start the engine and warm up it to normal working temperature. Resistance should be lower (usually from 270 to 400 Ohm).

If restrictive access to the sensor of temperature complicates connection to its contacts electric щупов, remove the sensor as it is described below, and make check in capacity with the warm water simulating operating conditions.


Before the beginning of this procedure wait complete cooling of the engine.

Replacement

 PERFORMANCE ORDER

  1. For removal of the sensor press a spring stopper, disconnect the electric socket, then carefully turn out the sensor. Be ready to an effluence of a small amount of a cooler; for reduction of an effluence prepare the new sensor and establish it as soon as possible.

Address with the cooler sensor very carefully. Damage of this sensor will affect work of all system of injection of fuel.


Before removal of the sensor it can be demanded to merge from a radiator a small amount of a cooler.

  1. Before installation of the sensor be convinced that its carving pure and put on it a small amount of a compound.
  2. Installation is return to removal.

Sensor of concentration of oxygen

General description

Usually sensors of oxygen are established on cars with the catalytic converter. The majority of sensors of oxygen are located in an exhaust pipe behind a final collector. On model 535 the sensor of oxygen is established in the catalytic converter. The electric socket of the sensor for simplification of access is turned towards the forward panel (left side).


The oxygen sensor (it is shown by an arrow) is usually located in an exhaust pipe behind a final collector, traces concentration of oxygen in exhaust gases.

Oxygen in exhaust gases cooperates with the sensor of oxygen and creates the tension changing from 0.1 In (high concentration of oxygen, a poor mix) to 0.9 In (low concentration of the oxygen, a rich mix). ECU constantly traces this change of tension to define an oxygen and fuel ratio in a mix. ECU, operating duration of an impulse of opening of fuel injectors (opening time) changes the air relation / a fuel mix. The fuel mix from 14.7 parts of air and 1 part of fuel is an ideal mix for minimization of toxicity of the fulfilled gases, allowing the catalytic converter to work with the greatest efficiency. This relation 14.7 to 1 ECU and the sensor of oxygen try to support all the time.

The sensor of oxygen does not develop any tension if its temperature is lower than the normal worker about 320 ° S.Vo vremya of this initial stage of warming up of ECU works in a mode of “an open contour” (that is, without information from the sensor).

When the engine gets warm to normal working temperature and/or worked within two or more minutes and if the sensor of oxygen develops constant tension below 0.45 In at 1500 rpm or big turns, memory of codes of refusals of ECU becomes more active.

If there is a problem with the sensor of oxygen or its chain, ECU works in a mode of “an open contour”, that is it operates supply of fuel according to the programmed value of codes of refusals instead of information from the oxygen sensor.

The correct operation of the sensor of oxygen depends on four conditions:

  1. The electric - the Low voltage developed by the sensor, depends on high-quality, pure contacts which it is necessary to check every time at suspicion or detection of misoperation of the sensor.
  2. Intake of external air - the Design of the sensor provides intake of air in an internal part of the sensor. Every time at removal of the sensor be convinced that air channels are not corked.
  3. The correct working temperature - ECU does not react to signals of the sensor of temperature while it will not get warm, approximately, to 320 ° by Page. This factor should be considered at an assessment of operability of the sensor.
  4. Unleaded fuel - Application of unleaded fuel is essential to the correct operation of the sensor. Be convinced that you apply such fuel.

In addition to the conditions given above the special attention should be turned on sensor service.

  • The sensor of oxygen is equipped with a cable with the electric socket which should not be disconnected from the sensor. Damage or a cable or socket detachment adversely affects operation of the sensor.
  • Greasing, dirt or other extraneous substances are inadmissible on the electric socket and on the punched end of the sensor.
  • Do not apply on the sensor clearing solvents of any type.
  • Do not drop the sensor and address with it carefully.
  • It is necessary to establish a silicone cover correctly that it did not melt and the sensor worked correctly.

Check

 PERFORMANCE ORDER

  1. Warm up the engine and leave it to idle. Disconnect from the oxygen sensor the electric socket and connect to target contact of the sensor positive щуп the voltmeter (address to the following table), and negative щуп - to the case. The oxygen sensor, being heated-up (to 320 ° C), develops very small signal of tension. Usually tension of a signal is in limits from 0.1 to 1.0 In).

Options of sockets of sensors of oxygen from a cable. For procedures of checks use the corresponding contacts of the sensor (there are three various four-wire sockets of sensors of oxygen - do not mix them).


Electric sockets of the majority of sensors of oxygen are located in a back part of the engine near the forward panel. Find a big rubber cover with a thick cable. On early models 535i the socket of a chain of a heater of the sensor of oxygen is under the car. Find a small protective cover. These models should have own sensor of oxygen that access to it was analogous with other models. About additional information consult at the dealer.

  1. Tracing tension, increase, and then reduce engine turns.
  2. At increase in turns tension should increase to 0.5 - 1.0 V.Pri decrease in turns tension should decrease to 0 - 0.4 Century.
  3. If it is applied, examine a heater of the sensor of oxygen (model with multiwire sensors). At the included ignition disconnect the electric socket of the sensor of oxygen and connect to the contacts specified in the table (look below), the voltmeter. Between contacts there should be a tension of the battery (approximately, 12 In).
  4. If indications wrong, check the relay of a heater of the sensor of oxygen (look Head System of onboard electric equipment). If information on the relay is inaccessible, determine an exact arrangement of the relay of a heater of the sensor of oxygen by the management for the owner of the car. On the relay tension of the storage battery should arrive.
  5. If the sensor of oxygen does not pass at least one of these checks, replace the sensor.

Replacement

Due to that: that the sensor is established in a final collector, the converter or a pipe which are compressed when cooling, the sensor of oxygen can appear very difficult to turn out on the cold engine. Instead of risking to damage the sensor (if you plan to use it again in other collector or a pipe), start the engine and let's work minute or two, then muffle it. Do not burn at performance of the following procedure.


 PERFORMANCE ORDER

  1. Disconnect a negative wire of the storage battery.

If the radio receiver on your car is equipped with system of protection against abduction, before shutdown of the storage battery be convinced that the correct code of activization is known. Before a detachment of a wire apply for information to the Section System of protection of an audiosystem from theft and language of an instrument guard.


If after battery connection on the display of the dashboard there is a message in other language, for procedure of installation of language address to the Section System of protection of an audiosystem from theft and language of an instrument guard.

  1. Lift the car and establish it on supports.
  2. Disconnect from the sensor the electric socket.
  3. Carefully unscrew the sensor.

Excessive the effort can damage a carving.

  1. For simplification of the subsequent removal it is necessary to put a high-temperature anticorrosive compound on a carving of the sensor. The carving of the new sensor is already covered with such compound but if the old sensor acts in film and established, put on a carving a compound.
  2. Establish the sensor and hardly tighten it.
  3. Attach to the main cable of the engine the electric socket of a cable of the sensor.
  4. Lower the car and connect the battery.
Type of the sensor of oxygen Target signal of the sensor A heater food (12 In)
Not warmed up (single-wire) black wire () no
Warmed-up (three-pro-water) contact 1 () contacts 3 () and 2 (-)
Warmed-up (four-pro-water) contact 2 () contacts 4 () and 3 (-)

Sensor of provision of a throttle (TPS)

General description

The sensor of provision of a throttle (TPS) is located on the end of a shaft of a throttle in the throttle case. Tracing target tension of TPS, ECU can define on the basis of knowledge of an angle of rotation of the valve of a throttle supply of fuel (set by the driver). In this TPS system works in a bigger measure as the switch, than as a potentiometer. One group of contacts of the switch of the valve of a throttle is closed (connection of contacts) only idling. The second group of contacts becomes isolated at complete opening of a throttle. Between these positions both of group of contacts are opened (there is no connection). Spoiled or weakened TPS can cause unstable injection of fuel and unstable turns of idling as ECU will decide that the throttle moves.

All models (except early models 535i with automatic transmission) have the incorporated switch of idling and a full throttle; the separate switch of idling indicates a throttle closed position while TPS is used for designation of a full open throttle. On models 535i with automatic transmission of TPS it is connected directly to the control unit of automatic transmission. At completely open throttle the control unit of transmission sends a signal about an open throttle to the block of control of Motronic.

All models, except early 535i with automatic transmission

Check

TPS of L-Jetronic system is located under the inlet pipeline (contacts are shown).

 PERFORMANCE ORDER

  1. Disconnect from TPS the electric socket and connect to contacts 2 and the 18th ohmmeter. Check short circuit between contacts 2 and 18 at the closed throttle (the late system Motronic is shown).
  1. Slightly slightly open a hand a throttle. Slowly release a throttle that to a stopper remained 0.2 - 0.6 mm. The ohmmeter should show short circuit.
  1. Check resistance between contacts 3 and 18 at an open throttle. There should be a short circuit within 8-12 degrees from completely open situation. If indications wrong, adjust TPS.
  1. If all indications of resistance correct and TPS is correctly adjusted, check a sensor food (5 In) and if necessary see wires between the sensor and ECU (look Head System of onboard electric equipment).

Adjustment

 PERFORMANCE ORDER

  1. If adjustment does not correspond (item 1-2) requirements, weaken TPS screws and turn the sensor in the correct situation. Follow procedure of check of TPS given above, and, having finished adjustment, tighten screws.
  2. Check TPS once again; if indications correct, attach the socket of a cable of TPS.

Early models 535i with automatic transmission

Check

 PERFORMANCE ORDER

  1. At first check TPS short circuit. For check of short circuit execute item 1-2 procedures.
  2. Further check the switch of provision of idling. Disconnect the socket of a cable of the switch of provision of idling and connect to contacts 1 and the 2nd ohmmeter. There should be a short circuit. Slightly slightly open a throttle and measure resistance. Short circuits should not be.

The switch of provision of idling and TPS on early models 535i with automatic transmission.

  1. Check correctness of signals of target tension of TPS at the closed throttle and the included ignition. Connect щуп the voltmeter to contact 3 (a black wire) from the back party of the TPS socket and check tension concerning the case. There should be 5 V.Takzhe, check tension between contact 3 (a black wire) and contact 1 (a brown wire). Here too there should be 5 Century.
  2. Check tension between contact 2 (a yellow wire) and contact 1 (a brown wire) and slowly open a throttle. Tension should raise constantly from 0.7 In (the throttle is closed) to 4.8 In (the throttle is completely open).

Adjustment

 PERFORMANCE ORDER

  1. First, measure the stabilized tension. At the included ignition and completely closed throttle measure tension between contact 3 (a black wire) and contact 1 (a brown wire). It should make about 5 Century.
  2. Further, weaken screws of fastening of the sensor and connect between contact 2 (a yellow wire) and contact 3 (a black wire) the voltmeter. At completely open throttle rotate the switch until tension does not become on 0.20 - 0.24 In less stabilized tension.

For measurement of such little changes of tension the digital voltmeter is required.

  1. Check TPS once again; if indications correct, attach to TPS the electric socket. Expediently paint or a compound for fixing of carvings to stop TPS screws.

Measuring instrument of a stream of air

General description

The measuring instrument of a stream of air is located in an inlet air line. The measuring instrument of a stream of air measures amount of the air arriving in the engine. ECU uses this information for management of supply of fuel. A large amount of air means acceleration while the small amount of air means delay or idling. Concerning all diagnostic checks and replacement procedures for a measuring instrument of a stream of air address to Head the Power supply system.

Sensors of the moment of ignition

The ignition moment in Motronic systems copes in the electronic way and to adjustment is not subject. At start the sensor of provision of a cranked shaft transmits a signal in ECU and the initial point of the moment of ignition is defined by it. When the engine works, the ignition moment continuously changes depending on various entrance signals in ECU. Turns of the engine are defined by the sensor of turns. In early systems Motronic the reperny sensor and the sensor of turns are established over a flywheel on a coupling case. In late systems Motronic there is a uniform sensor (the sensor of impulses), established over a pulley of a cranked shaft. This sensor works as the sensor of turns and as the situation sensor. For additional information address to Head ignition System.

Some models are equipped with the VMT sensor in a forward part of the engine. This sensor belongs to the block of service testing of BMW and is not a part of system of ignition of Motronic.


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6.5. System of ventilation of a case (PCV)