E46 series BMW 3

since 1998 of release

Repair and car operation

E46 series BMW 3
+ BMW 3 Cars (E46)
+ Current leaving and service
+ Engine
+ Systems of cooling, heating
+ Power supply systems, injection and release
- Engine electric equipment
   General information and security measures
   - System of electronic control by ignition and injection of the petrol engine
      The main data on system of electronic control by the engine
   + ignition System
   + System of preheat of the diesel engine
   + charge and start Systems
+ RKPP and transmission line
+ Automatic transmission
+ Coupling and power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ electric equipment Schemes


System of electronic control by ignition and injection of the petrol engine

The main data on system of electronic control by the engine

System of an electronic digital control petrol engine (DME)

1 — an adsorber
2 — the locking valve
3 — the valve of ventilation of a fuel tank
4 — a regulator of pressure of fuel
5 — an injector
6 — a pressure zadatchik
7 — the ignition coil
8 — the situation sensor
9 — the pump of secondary air
10 — the locking valve
11 — a measuring instrument of weight of air
12 — a monitor
13 — the butterfly valve sensor

14 — an idling zadatchik
15 — the air temperature sensor
16 — the valve of a retsirkulyatsiya of the fulfilled gases
17 — the fuel filter
18 — the detonation sensor
19 — the sensor of number of turns
20 — the sensor of temperature of the engine
21 — the oxygen sensor
22 — the diagnostic socket
23 — a diagnostic control lamp
24 — the differential sensor of pressure
25 — the fuel pump

The electronic control system of the engine allows:

- To reduce the content of harmful substances in the fulfilled gases thanks to an exact task of the moment of ignition in any operating conditions of the engine.
- To increase capacity of a spark of ignition on the petrol engine and therefore reliability of start and stability of its work.
- Self-diagnostics of a control system by the engine, provides possibility of fast troubleshooting. The control system of the engine has memory of malfunctions. If defect in use comes to light, it is brought in memory of the device. By means of special devices it is possible to deduce the list of the malfunctions, allowing to eliminate defect independently. Address also to the Section Diagnostics of malfunctions. Work it is desirable to lead HUNDRED in conditions.

The control unit the engine represents the minicomputer with high speed. It, besides other, defines the optimum moment of ignition on the petrol engine, and on a diesel engine by means of the relay includes glow plugs. Thus there is a coordination of operation of the control unit with other systems of the car, for example, to a control system of a check point or blocking from stealing.

Elements of a control system of the engine keeps the high performance for a long time and practically does not demand service. Replacements, at carrying out maintenance, demand only a spark plug. Serious works on adjustment and repair demand use of difficult diagnostic devices. Address to the Section Diagnostics of malfunctions. Works it is desirable to lead HUNDRED in conditions.
Correction of the moment of ignition on petrol engines, within carrying out maintenance, is not required.

Owing to good starting characteristics of the diesel engine with direct injection preliminary heat is required generally at temperatures below 0°С.

Information arriving from various sensors, and the teams arriving to executive bodies, provide optimum operation of the engine in any mode. If sensors fail, the monitor is switched in emergency operation to exclude damages of the engine and to provide possibility of further movement of the car. Failure of sensors not necessarily should be felt on deterioration of operation of the engine.
However no later than the closest review period of the fulfilled gases (AU) data on it will be brought in memory of malfunctions of a control system by the engine.

- The system of ignition has no the mobile parts, the traditional distributor of ignition is absent. Each spark plug has the coil.
- The monitoring system of tension of ignition at too low voltage disconnects the DME block (for example, owing to cable damage). Thus the engine cannot be started. It excludes damages of the catalytic converter.
- The system of anti-detonation regulation serves for definition and regulation of optimum time of ignition for each cylinder. If there is a malfunction in ignition system, supply of fuel to the corresponding cylinder stops.
- The relay of the fuel pump is in the relay block over a ware box. The relay submits a current to the fuel pump.

General description of system of self-diagnostics of OBD

1 the structure of OBD system includes some diagnostic devices making monitoring of separate parameters of systems of decrease in toxicity and fixing revealed refusals in memory of the onboard processor in the form of individual codes of malfunctions. The system makes also check of sensors and actuation mechanisms, supervises vehicle service cycles, provides storing possibility even failures quickly arising in the course of work and cleaning of the block of memory.
2 All petrol models described in the real Management are equipped with system of onboard diagnostics of the second generation (OBD-II). A basic element of system is the onboard processor more often called by the electronic module of management (ESM), or the module of management of functioning of the power unit (RSM). RSM is a brain of a control system of the engine. Basic data arrive on the module from various information sensors and other electronic components (switches, the relay etc.) . On the basis of the analysis of data arriving from information sensors and according to put in memory of the processor in base parameters, RSM develops commands for operation of various operating relays and actuation mechanisms, carrying out thereby adjustment of working parameters of the engine and providing maximum efficiency of its return at the minimum fuel consumption. Data read-out of memory of the OBD-II processor is made by means of the special scanner connected to the 16-contact diagnostic socket of reading of a database (DLC), located under the dashboard from the driver's party of the car, or to the 20-contact socket located at the left in an impellent compartment. Address to the section Diagnostics of malfunctions.

In principle, reading written down in memory of system of self-diagnostics of codes of malfunctions can be made by means of a lamp “Check the engine”.

3 On service of components of control systems of engine/decrease in toxicity of the fulfilled gases special guarantee certificates with the prolonged validity period extend. It is not necessary to undertake attempts of independent performance of problem diagnostics of RSM or replacement of components of system, to an exit of terms of these obligations, - address to specialists of firm car repair shops.

Information sensors

4 Oxygen sensors (l-probes) - the Sensor are developed by a signal which amplitude depends on a difference of the content of oxygen (О2) in the fulfilled gases of the engine and external air before and after the catalytic converter.

5 Sensor of provision of a cranked shaft (SKR) - the Sensor informs RSM on the provision of a cranked shaft and engine turns. This information is used by the processor at definition of the moments of injection of fuel and installation of a corner of an advancing of ignition.

6 Sensor of position of pistons (CYP) - on the basis of the analysis of signals of RSM arriving from the sensor calculates position of the piston of the first cylinder and uses this information at definition of the moments and sequence of injection of fuel in chambers of combustion of the engine.
7 VMT Sensor (TDC) - signals Developed by the sensor are used by RSM at definition of installations of a corner of an advancing of ignition at the moment of engine start.

8 Sensor of temperature of cooling liquid of the engine (eats) - on the basis of information ESM/RSM arriving from the sensor carries out necessary corrections of structure of an air and fuel mix and a corner of an advancing of ignition, and also supervises EGR system work.

9 Sensor of temperature of soaked-up air (IAT) - RSM uses information arriving from the IAT sensor at corrections of a stream of fuel, installations of a corner of an advancing of ignition and management of EGR system functioning.

10 Sensor of provision of a butterfly valve (TPS) - the Sensor is located on the case of a throttle and connected to a butterfly valve axis. By amplitude of given-out TPS of a signal of RSM determines a corner of opening of a butterfly valve (copes the driver from a gas pedal) and as appropriate corrects supply of fuel to inlet ports of chambers of combustion. Failure of the sensor, or weakening of its fastening leads to interruptions of injection and violations of stability of turns of idling.

11 Sensor of absolute pressure in the pipeline (MAR) - the Sensor supervises variations of depth of depression in the inlet pipeline, connected with changes of turns of a cranked shaft and load of the engine and will transform received information to a peak signal. RSM uses information delivered by MAR and IAT sensors at thin corrections of supply of fuel.
12 Barometric sensor of pressure - the Sensor develops the peak signal proportional to changes of atmospheric pressure which is used by RSM at determination of duration of the moments of injection of fuel. The sensor is built in the RSM module and to service in an individual order is not subject.

13 Sensor of a detonation - the Sensor reacts to change of level of the vibrations connected with detonations in the engine. On the basis of information of RSM arriving from the sensor carries out the corresponding correction of a corner of an advancing of ignition.

14 Sensor of speed of movement of the car (VSS) - As appears from its name, the sensor informs the processor on the current speed of movement of the car.

15 Sensor of size of opening of the EGR valve - the Sensor notifies RSM on size of shift of a plunzher of the EGR valve. Received information is used then the processor at management of functioning of system of a retsirkulyatsiya of the fulfilled gases.
16 Sensor of pressure in a fuel tank - the Sensor is a component of system of catching of fuel evaporations (EVAP) and serves for pressure tracking паров gasoline in a tank. On the basis of information of RSM arriving from the sensor gives out commands for operation of electromagnetic valves of a purge of system.
17 Sensor switch of pressure of system of hydrostrengthening of a wheel (PSP) - on the basis of information of RSM arriving from the PSP sensor switch provides increase of turns of idling at the expense of IAC sensor operation for the purpose of compensation of increasing loads of the engine, connected with functioning of the steering hydraulic booster at commission of maneuvers.
18 Transmission sensors - In addition to the data arriving from VSS, RSM receive also information from sensors placed in a transmission, or connected to it. Number of such sensors treat: (а) sensor of turns of a secondary (radical) shaft and (b) sensor of turns of an intermediate shaft.
19 Sensor switch of management of turning on of the coupling of coupling of the conditioner of air - When giving food from the battery to the electromagnetic valve of the To/to compressor the corresponding information signal arrives on RSM which regards it as the certificate of increase of load of the engine and as appropriate corrects turns of its idling.
Actuation mechanisms
20 Main PGM-FI relay (the relay of the fuel pump) - RSM makes activation of the relay of the fuel pump at an ignition key povorachivaniye in the situation START or RUN. At ignition inclusion activation of the relay provides pressure lifting in a power supply system. More detailed information on the main relay is provided in Head of the Power supply system, injection and release.
21 Injectors of fuel - RSM provides individual inclusion of each of injectors according to an ignition established order. Besides, the module supervises duration of opening of the injectors, defined in the width of an operating impulse measured in milliseconds and defining amount of fuel injected into the cylinder. More detailed information on a principle of functioning of system of injection, replacement and service of injectors is provided in Head of the Power supply system, injection and release.
22 Module of management of ignition (ICM) - the Module operates functioning of the coil of ignition, defining a demanded base advancing on the basis of developed RSM of teams. On all models of cars considered in the real Management it is used built in the distributor of ignition of ICM, is more detailed in the present Chapter.

23 Valve of stabilization of turns of idling (IAC) - the IAC Valve carries out a dosage of amount of the air which is restarted up bypassing a butterfly valve when the last is closed, or occupies the provision of idling. Opening of the valve and formation of a rezultiruyushchy air stream RSM operates.

24 Electromagnetic valve of a purge of a coal adsorber - the Valve is a component of system of catching of fuel evaporations (EVAP) and, working at the command of RSM, carries out release accumulated in an adsorber паров fuels in the inlet pipeline for the purpose of burning them in the course of normal functioning of the engine.
25 Electromagnet of management of a purge of a coal adsorber - the Electromagnet is used by RSM at check by OBD-II system of serviceability of functioning of EVAP system.

Reading of codes of malfunctions

26 At detection of the malfunction repeating in a row on two trips, RSM gives out command for inclusion of the control lamp built in in an instrument guard “Check the engine”, called also the indicator of refusals. The lamp will continue to burn until memory of system of self-diagnostics will not be cleared of the codes of the revealed malfunctions brought in it (address to Specifications). Reading of codes of malfunctions in OBD-II system can be made in the various ways. The main way is reading by means of described in the Section Diagnostics of malfunctions of the devices connected to the 16-contact DLC socket of OBD-II system. Other ways are possible not on all models. The blinking code (defined by the producer and distinct from codes of "R" of the SAE standard) can be считан on a lamp “Check the engine”.


27 without starting the engine, include ignition, - a control lamp “Check the engine” should light up, otherwise it is necessary to replace it. Having checked serviceability of a condition of a lamp, again switch off ignition.

Method of reading of blinking codes by a lamp “Check the engine” (it is possible on some models)

28 After ignition inclusion five times within five seconds completely squeeze out and release an accelerator pedal. If in memory of the processor codes of taking place malfunctions are brought, they will start to be highlighted consistently by a control lamp “Check the engine” on a control panel of the car. Consider a blinking code.

The lamp expects 5 seconds, one flash follows, then the code with intervals of 2.5 seconds between categories stands out. After code delivery a lamp it is necessary to burn. Repeat procedure to consider the subsequent codes. If the first given-out code 1444, 2444 or 4444 - malfunctions are not fixed.
The codes 1000 or 2000 which are given out by one or two flashes and a long pause, and then continuous burning of a lamp, indicate the completion of delivery of a code.

Blinking codes, differ from the codes "R" given in Specifications.

Engine start automatically interrupts access to diagnostics system.

Cleaning of memory of OBD-II

29 When entering a code of malfunction in memory of RSM on an instrument guard of the car the control lamp “Lights up check the engine”. The code remains written down in memory of the module.
30 For cleaning of memory of ESM connect to system the scanner and choose in its menu the CLEARING COEDS function (Removal of codes). Further follow the instructions highlighted on the device, or at once for 30 seconds take from the nest in the assembly block EFI safety lock. Alternatively cleaning of memory of system can be made by a way of removal of a fusible insert (the main safety lock of system of onboard power supply), the battery established near the positive plug (see. Head Onboard electric equipment) (it is possible to disconnect also simply from the battery a positive wire).

It is necessary to mean that when cleaning memory of OBD by a detachment of a negative wire from the battery, adjusting parameters of the engine are erased and stability of its turns for short time after primary start is broken.

If the stereosystem established on the car is equipped with a security code before disconnecting the battery, make sure that have the correct combination for audiosystem input in action!

Battery shutdown also leads to removal of settings of the receiver on favourite radio stations.

In order to avoid ESM damage its shutdown and connection should be made only at the switched-off ignition!

31 Track, that memory of system was cleared before installation on the engine of new components of systems of decrease in toxicity of the fulfilled gases. If before system start after replacement of the failed information sensor not to make cleaning of memory of refusals, RSM will bring in it a new code of malfunction. Cleaning of memory allows the processor to make change-over on new parameters. Thus the first 50-20 minutes after primary start of the engine some violation of stability of its turns can take place.