Subaru Forester

1997-2005 of release

Repair and car operation



Subaru Forester
+ Cars Subaru Forester
+ The maintenance instruction
+ Routine maintenance
+ The engine
+ Systems of cooling, heating
+ The power supply system and release
+ Engine electric equipment
- Control systems of the engine
   Specifications
   System of onboard diagnostics (OBD) - a principle of functioning and codes of malfunctions. Signals in management chains
   ЕСМ - the general information, an estimation of a condition and replacement
   Information gauges, the relay and actuation mechanisms - the general information
   System of catching of fuel evaporations (EVAP)
   System recycling the fulfilled gases (EGR)
   System of operated ventilation картера (PCV)
   The conductor of a jellied mouth of a fuel tank
   The Katalitichesky converter - the general information, check of a condition and replacement
+ Gear change box
+ Coupling, трансмиссионная a line
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
3df4be34


System of onboard diagnostics (OBD) - a principle of functioning and codes of malfunctions. Signals in management chains

Data on diagnostic devices

Check of serviceability of functioning of components of systems of injection and decrease in toxicity of the fulfilled gases is made by means of a universal digital measuring instrument (multimeter).

Use at diagnostics of considered systems of a digital multimeter with a high impedance essentially raises accuracy made in низковольтовом a range of measurements



Use of a digital measuring instrument preferably for the several reasons. First, on analogue devices it is difficult enough (at times, it is impossible), to define result of the indication to within the 100-th and thousand shares while at inspection of the contours including in the structure electronic components, such accuracy takes on special significance. The second, the reason that fact is not less important that the internal contour of a digital multimeter, has high enough impedance (internal resistance of the device makes 10 мОм). As the voltmeter is connected to a checked chain in parallel, accuracy of measurement by that above, than the smaller current will pass through actually device. The given factor is not essential at measurement concerning high values of pressure (9 12), however there is defining at diagnostics of elements giving out low-voltage signals, such, as, for example, a l-probe where it is a question of measurement of shares of volt.

Parallel supervision of parametres of signals, resistance and pressure in all chains of management is possible by means of a splitter included consistently in a socket of the block of engine management. Thus on the switched off, working engine or during car movement, measurement of parametres of signals on splitter plugs from what the conclusion about possible defects becomes is made.

For diagnostics of electronic systems of the engine, automatic transmission, ABS, SRS special diagnostic scanners or testers with the certain cartridge, intended for work with system of onboard diagnostics of the second generation OBD II, special scanner Subaru Select Monitor (SSM) or the personal computer with a special cable and the program browser OBD (www.obd-2.com, www.obd-2.de) are applied.

Universal adapter K-L-line


Connection of the personal computer to a diagnostic socket


Universal adapter K-L-line (www.autoelectric.ru), serves for the coordination of signals of port RS-232 and interfaces ISO-9141 (K-line) and ALDL. The various cables necessary for diagnostics of concrete mark of the car can be connected To adapter sockets. The switches established in the adapter and indication elements allow to choose necessary operating modes and approximately to estimate work of target lines. So, the luminescence of a green light-emitting diode with marks L-line, testifies to connection of line L with the car case. The luminescence of a red light-emitting diode with marks K-line specifies in high potential which blinking of indicators is present during this moment on K.Pri's line of the established communication with the car can be imperceptible for an eye because of high speed of an exchange. Connection to the computer is made directly in 25-contact COM-port or with the help “Cable RS-232 25 конт. - 9 конт.” In a 9-contact CATFISH-PORT.

Some scanners, besides usual operations of diagnostics, allow, at connection with the personal computer, to unpack stored in memory of the block of management basic schemes of an electric equipment (if are put), to program anticreeping system and management blocks, to observe signals in car chains in real time.

II for diagnostics of your car you can download the free version of browser OBD also from our site arus.spb.ru

Reading written down in memory of system of self-diagnostics of codes of malfunctions on some models can be made also on the indicator “Check up the engine” on a control panel.

Appointment of conclusions of a diagnostic socket.

Diagnostic socket of system of onboard diagnostics OBD II

№ a conclusion

Appointment

1
Battery plus. Energised at any position of the lock of ignition.
4
Signal from the management block to Subaru Select Monitor (a tester of diagnostics of firm Subaru)
5
Signal from Subaru Select Monitor to the management block
6
Clock signal Subaru Select Monitor
10
Line To, ISO 9141 CARB
12
The case - an alarm conclusion
13
Connection with the case

The general description of system OBD II

System OBD structure includes some the diagnostic devices making monitoring of separate parametres of systems of decrease of 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 gauges and actuation mechanisms, supervises vehicle service cycles, provides storing possibility even failures quickly arising in the course of work and clearing of the block of memory.

Models described in the present Management are equipped by system of onboard diagnostics (OBD). A system Basic element is the onboard processor, more often named the electronic module of management (ЕСМ), or the module of management of functioning of the power unit (РСМ). РСМ is a brain of a control system of the engine. The initial data arrives on the module from various information gauges and other electronic components (switches, the relay etc.) . On the basis of the analysis of the data arriving from information gauges and according to put in memory of the processor in base parametres, РСМ develops commands on operation of various operating relays and actuation mechanisms, carrying out thereby updating of working parametres of the engine and providing peak efficiency of its return at the minimum expense of fuel. Data read-out of memory of processor OBD-II is made by means of the special scanner connected to a 16-contact diagnostic socket of reading of a database, located under the panel of devices from the driver's party of the car.

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

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

Reading of codes of malfunctions

The information maintenance of categories of a code

The characteristic

Value

Kind P 0 3 8 0 from left to right:
1
The category
P
The power unit
B
Body
WITH
The chassis
2 category
Code source
0
Standard – set SAE
1
Expanded – set Subaru
3 category
System
0
System as a whole
1
подмешивания air (air/fuel induction)
2
Fuel injection
3
cистема ignitions or ignition admissions
4
The additional control of release (auxillary emission
control)
5
Speed of the car and management х.х.
6
Entrance and target signals of the block of management
7
Transmission
4,5 categories
Serial number of malfunction of a component or chain (00-99)

At revealing of the malfunction repeating successively on two trips, РСМ gives out a command on inclusion of the control lamp built in in an instrument guard “Check up the engine”, named 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.

If the lamp blinks with frequency of 1 Hz - the system has registered the ignition admissions, able to lead to damage каталитического the converter.

At the included ignition, the stopped engine and the connected socket of a mode of check - the lamp blinks with frequency of 3 Hz.

Reading of codes of malfunctions in system OBD-II can be made in the various ways. The basic way is reading by means of described above the devices connected to a diagnostic socket.

Socket of a mode of testing (1) and a 16-contact diagnostic socket of a database (DLC) located under the panel of devices, near to a steering column.

The blinking code can be считан on a control lamp, after connection of a test socket, as is shown in an illustration.


Without starting the engine, include ignition, - a control lamp “Check up the engine” should light up, otherwise it is necessary to replace it, and to go out after engine start. The lamp can not die away for the reason of short closed stopper of a mouth of a fuel tank.

Having checked up serviceability of a condition of a lamp and the closed condition of a stopper of a mouth, again warm up the engine and switch off ignition. Close a test socket. Get the car and be passed 1 mines with a speed more than 10 km/hour, serially including all transfers. Stop, without switching off the engine. On 40 сек lift turns to 2000 in minute Consider blinking codes (address to Specifications).

Clearing of memory OBD

At entering of a code of malfunction in memory РСМ on an instrument guard of the car the control lamp “lights up Check up the engine”. The code remains written down in memory of the module.

For clearing of memory ЕСМ connect to system the scanner and choose in its menu function CLEARING COEDS (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 safety lock EFI. Alternatively clearing of memory of system can be made by removal of a fusible insert (the main safety lock of system of onboard power supplies), it is possible to disconnect from the battery a positive wire simply also.

It is not desirable to make clearing of memory OBD by a detachment of a negative wire from the battery as it will lead to deleting of adjusting parametres of the engine and infringement of stability of its turns for short time after primary start.

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

Battery switching-off also leads to removal of options of the receiver on favourite radio stations.

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

Track, that memory of system has been cleared before installation on the engine of new components of systems of decrease in toxicity of the fulfilled gases. If before start of system after replacement of the failed information gauge not to make clearing of memory of refusals, РСМ will bring in it a new code of malfunction. Memory clearing allows the processor to make change-over on new parametres. Thus in the first 50 20 minutes after primary start of the engine can take place some infringement of stability of its turns.

Application of an oscillograph for supervision of signals in chains of control systems

Digital multimeters perfectly approach for check of electric chains being in a static condition, and also for fixing of slow changes of traced parametres. At carrying out of the dynamic checks which are carried out on the working engine, and also at revealing of the reasons sporadic failures by absolutely irreplaceable tool there is an oscillograph.

Some oscillographs allow to keep oscillograms in the built in module of memory with the subsequent conclusion of results to the press or their swapping to the carrier of the personal computer already in stationary conditions.

The oscillograph allows to observe periodic signals and to measure pressure, frequency, width (duration) of rectangular impulses, and also levels of slowly varying pressure.

The oscillograph can be used for:
  • Revealings of failures of astable character.
  • Checks of results of the made corrections.
  • Monitoring of activity of a l-probe of a control system of the engine equipped catalytic with the converter.
  • The analysis of the signals developed by a l-probe which deviation of parametres from norm is unconditional the certificate of infringement of serviceability of functioning of a control system as a whole, - on the other hand, correctness of the form of impulses given out by a ljambda-probe can serve as a reliable guarantee of absence of infringements in a control system.
  • Reliability and simplicity of operation of modern oscillographs do not demand any special special knowledge and experience from the operator. Interpretation of the received information can be easily made by elementary visual comparison of the oscillograms removed during check with resulted more low typical for various gauges and actuation mechanisms of automobile control systems of time dependences.

    Parametres of periodic signals

    Characteristics of any periodic signal

    Each signal removed by means of an oscillograph can be described by means of the following key parametres:

  • Amplitude: the Difference of the maximum and minimum pressure () a signal within the period;
  • The period: Duration of a cycle of a signal (мсек)
  • Frequency: Quantity of cycles in a second (Hz);
  • Width: Duration of a rectangular impulse (мс, мкс);
  • Porosity: the Relation of the period of repetition to width (In foreign terminology return is applied porosity parametre named a running cycle, expressed in %)
  • The signal form: Sequence of rectangular impulses, individual emissions, a sinusoid, sawtooth impulses, etc.;
  • Usually characteristics of the faulty device strongly differ from reference that allows the operator easily and quickly visually to reveal the refused component.

    Direct current signals - pressure of a signal is analyzed only.

    This sort of signals are developed by following devices:

    The gauge of temperature of a cooling liquid of the engine (ECT)

    The gauge of temperature of soaked up air (IAT)

    The gauge of position throttle заслонки (TPS)

    Warmed up l-probe (the oxygen gauge)

    Measuring instrument of the volume expense of a stream of air (VAF)

    Measuring instrument of weight of air (MAF)

    Alternating current signals - are analyzed amplitude, frequency and the signal form.

    The detonation gauge (KS)

    The inductive gauge of turns of the engine

    The frequency-modulated signals - are analyzed amplitude, frequency, the form of a signal and width of periodic impulses. Sources of similar signals are following devices:

    The inductive gauge of position of a cranked shaft (CKP)

    The inductive gauge of position of a camshaft (CMP)

    The inductive gauge of speed of movement of the car (VSS)

    Working on effect of the Hall gauges of turns and position of shaft

    Optical gauges of turns and position of shaft

    Digital gauges of thermometric measurement of weight of air (MAF) and absolute pressure in the inlet pipeline (MAP)


    The signals modulated on width of an impulse (ШИМ) - are analyzed amplitude, frequency, the form of a signal and porosity of periodic impulses. Sources of similar signals are following devices:

    Fuel injectors

    Devices of stabilisation of turns of idling (IAC)

    Primary winding of the coil of ignition

    The electromagnetic valve of a purge of a coal adsorber (EVAP)

    System valves recycling the fulfilled gases (EGR)

    The coded sequence of rectangular impulses - the amplitude, frequency, the form of sequence of separate impulses are analyzed.

  • This sort of signals are generated by the module of memory of self-diagnostics ECM of a control system of the engine.
  • By the analysis of width and the form of impulses, and also calculation of their quantity in each of groups can be считаны codes of malfunctions stored in memory (on an illustration - a code 1223).
  • The amplitude and the signal form remain the constants, the written down value will stand out until memory of the module will not be cleared.
  • Signal of a code of malfunction of the module of self-diagnostics of a control system of the engine (a code 1223)


    Interpretation of signals

    The form of a signal given out by an oscillograph depends on set of various factors and can change appreciably. In a kind told before to start replacement of a suspected component in case of discrepancy of the form of the removed diagnostic signal with the reference oscillogram, it is necessary to analyse the received result carefully:



    Digital signal

    Analogue signal


    Pressure


    Zero level of a reference signal cannot be considered as absolute basic value, - "zero" of a real signal, depending on concrete parametres of a checked chain, it can appear shifted concerning reference (see [1]) within a certain admissible range (see [2] and [1]).

    The full amplitude of a signal depends on pressure of a food of a checked contour and also can vary concerning reference value in certain limits (see [3] and [2]).


    In chains of a direct current the amplitude of a signal is limited to pressure of a food. As an example it is possible to result a chain of system of stabilisation of turns of idling (IAC) which alarm pressure does not change in any way with change of turns of the engine.

    In chains of an alternating current the amplitude of a signal already unequivocally depends on frequency of work of a source of a signal so, the amplitude of the signal which is given out by the gauge of position of a cranked shaft (CKP) will increase with increase of turns of the engine.

    In a kind told if the amplitude of a signal removed by means of an oscillograph appears excessively low or high (up to trimming of top levels), it is enough to switch only a working range of the device, having passed to a corresponding scale of measurement.

    At check of the equipment of chains with electromagnetic management (for example, system IAC) at food switching-off pressure throws (see [4]) which can be ignored easy at the analysis of results of measurement can be observed.

    It is not necessary to worry also at occurrence of such deformations of the oscillogram, as скашивание the bottom part of forward front of rectangular impulses (see [5]) if, of course, the fact выполаживания front is not a sign of infringement of serviceability of functioning of a checked component.


    Frequency

    Frequency of repetition of alarm impulses depends on working frequency of a source of signals.

    The form of a removed signal can be edited and led to a kind convenient for the analysis by switching on an oscillograph of scale of time development of the image.

    At supervision of signals in alternating current chains time development of an oscillograph depends on frequency of a source of a signal (see [3]), defined by engine turns.


    As already it was told above, for signal reduction to a legible kind it is enough to switch scale of time development of an oscillograph.

    In certain cases characteristic changes of a signal appear developed mirror concerning reference dependences that speaks реверсивностью polarity of connection of a corresponding element and, in the absence of an interdiction for change of polarity of connection, can be ignored at the analysis.

    Typical signals of components of control systems of the engine

    Modern oscillographs are usually equipped only by two alarm wires in a compartment with a set various probeов, allowing to carry out device connection practically to any device.

    The red wire is connected to a positive pole of an oscillograph and usually connected to the plug of the electronic module of management (ECM). The black wire should be connected to reliably earthed point (weight).



    Injectors

    Management of structure of an air-fuel mix in modern automobile electronic systems of injection of fuel is carried out by timely updating of duration of opening of electromagnetic valves of injectors.

    Duration of stay of injectors abroach is defined by duration developed by the module of management of the electric impulses submitted on an input of electromagnetic valves. Duration of impulses is measured in milliseconds and usually does not fall outside the limits a range 1 14 мс.

    Impulse of management of opening of an injector of injection of fuel


    Often on the oscillogram it is possible to observe also a series of the short pulsations following directly behind the initiating negative rectangular impulse and supporting the electromagnetic valve of an injector abroach, and also the sharp positive throw of pressure accompanying the moment of closing of the valve.

    Serviceability of functioning ECM can be checked easily up by means of an oscillograph by visual supervision of changes of the form of an operating signal at a variation of working parametres of the engine. So, duration of impulses at проворачивании the engine on single turns should be a little above, than at unit work on low turns. Increase of turns of the engine should be accompanied by respective increase in time of stay of injectors abroach. The given dependence is especially well shown at opening throttle заслонки by short pressing a gas pedal.

     PERFORMANCE ORDER

    1. By means of thin probeа from a set applied on an oscillograph connect a red wire of the device to инжекторной to plug ECM of a control system of the engine. Щуп the second alarm wire (black) oscillograph reliably earth.
    2. Analyse the form read out during time проворачивании the signal engine.
    3. Having started the engine, check up the form of an operating signal on single turns.
    4. Sharply having pressed a gas pedal, lift frequency of rotation of the engine to 3000 rpm, - duration of operating impulses at the moment of an acceleration should increase considerably, with the subsequent stabilisation at level equal, or hardly smaller peculiar to idling turns.
    5. Fast closing throttle заслонки should lead to the flattening of the oscillogram confirming the fact перекрывания of injectors (for systems with отсеканием fuel givings).


    At cold start the engine requires some enrichment of an air-fuel mix that is provided with automatic increase in duration of opening of injectors. In process of warming up duration of operating impulses on the oscillogram should be reduced continuously, gradually coming nearer to value typical for single turns.

    In injection systems in which the injector of cold start is not applied, at cold start of the engine the additional operating impulses shown on the oscillogram in the form of pulsations of variable length are used.

    In the table resulted more low typical dependence of duration of operating impulses of opening of injectors on a working condition of the engine is presented.

    Engine condition

    Duration of an operating impulse, мс

    Single turns 1.5 5
    2000 3000 rpm 1.1 3.5
    Full gas 8.2 3.5

    Inductive gauges

    The typical oscillogram of the signal developed by the inductive gauge


     PERFORMANCE ORDER

    1. Start the engine and compare the oscillogram removed from an exit of the inductive gauge with resulted on illustration reference.
    2. The increase in turns of the engine should be accompanied by increase in amplitude of a pulse signal developed by the gauge.


    The electromagnetic valve of stabilisation of turns of idling (IAC)



    In motor industry electromagnetic valves IAC of set of the various types which are giving out signals also of the various form are used.

    The general distinctive feature of all valves is that fact that porosity of a signal should decrease with loading increase for the engine, connected with inclusion of additional consumers of the capacity causing fall of turns of idling.

    If porosity of the oscillogram changes with loading increase, however at inclusion of consumers infringement of stability of turns of idling takes place, check up a condition of a chain of the electromagnetic valve, and also correctness given out ECM a command signal.

    Usually in chains of stabilisation of turns of idling the 4-polar step-by-step electric motor which description is resulted more low is used. Check of 2-contact and 3-contact valves IAC is made in a similar manner, however oscillograms of alarm pressure given out by them are absolutely unlike.

    The step-by-step electromotor, reacting on given out ECM a pulsing operating signal, makes step updating of turns of idling of the engine according to working temperature of a cooling liquid and current loading on the engine.

    Levels of operating signals can be checked up by means of an oscillograph, measuring probe which is connected serially to each of four plugs of the step-by-step motor.

    Warm up the engine to normal working temperature and leave its working on single turns.

    For increase in loading at the engine include head headlights, air conditioner, or, - on models with the wheel hydraulic booster, - turn a steering wheel. Idling turns should fall to short time, however there and then again to be stabilised at the expense of valve IAC operation.

    Compare the removed oscillogram with resulted on an illustration reference.



    The oscillogram of an operating signal of system of stabilisation of turns of idling (IAC)


    Ljambda-probe (the oxygen gauge)

    In Section the oscillograms typical for oxygen gauges most often used on cars циркониевого of type in which basic pressure 0.5В is not used are resulted. Recently the increasing popularity is got by titanic gauges, the working which range of a signal makes 0 5 In, and high level of pressure stands out at combustion of the impoverished mix, low, - enriched.


     PERFORMANCE ORDER

    1. Connect an oscillograph between the l-probe plug on ECM and weight.
    2. Make sure that the engine is heated-up to normal working temperature.
    3. Compare the oscillogram displayed a measuring instrument to the reference oscillogram of the signal which is given out by a typical ljambda-probe resulted on an illustration (the oxygen gauge).

    If the removed signal is not wavy, and represents linear dependence, that, depending on pressure level, it testifies to excessive repauperization (0 0.15), or reenrichment (0.6 1) an air-fuel mix.

    If on single turns of the engine the normal wavy signal takes place, try to squeeze out sharply some times педель gas, - signal fluctuations should not fall outside the limits a range 0 1 Century

    The increase in turns of the engine should be accompanied by increase of amplitude of a signal, reduction - decrease.

    The detonation gauge (KS)

     PERFORMANCE ORDER

    1. Connect an oscillograph between the plug of the gauge of detonation ECM and weight.
    2. Make sure that the engine is heated-up to normal working temperature.
    3. Sharply squeeze out a pedal of gas and compare the form of a removed signal of an alternating current to the reference oscillogram of the signal which is given out by the typical gauge of a detonation (KS).

    At insufficient image sharpness slightly knock on the block of cylinders around placing of the gauge of a detonation.

    If to achieve unambiguity of the form of a signal it is not possible, replace gauge KS, or check up a condition of electroconducting of its chain.

    Ignition signal on an amplifier exit

     PERFORMANCE ORDER

    1. Connect an oscillograph between the plug of the amplifier of ignition ECM and weight.
    2. Warm up the engine to normal working temperature and leave its working on single turns.
    3. On the oscillograph screen the sequence of rectangular impulses of a direct current should stand out. Compare the form of an accepted signal to the reference oscillogram of an operating signal of the amplifier of ignition, paying steadfast attention to coincidence of such parametres, as amplitude, frequency and the form of impulses.

    At increase in turns of the engine frequency of a signal should increase in direct ratio.

    Primary winding of the coil of ignition

    The signal oscillogram on the plug of a primary winding of the coil of ignition

     PERFORMANCE ORDER

    1. Connect an oscillograph between the plug of the coil of ignition ECM and weight.
    2. Warm up the engine to normal working temperature and leave its working on single turns.
    3. Compare the form of an accepted signal with ыэталонной the oscillogram of an operating signal of the amplifier of ignition, - positive throws of pressure should have constant amplitude.

    Non-uniformity of throws can be caused excessive resistance of a secondary winding, and also malfunction of condition ВВ of a wire of the coil or a candle wire.