LEXUS RX 300

1998 — 2003 of release

Repair and operation of the car



Lexus RX 300
+ Lexus RX-300 cars
+ Governing bodies and methods of operation
+ Settings and routine maintenance of the car
+ Engine
+ Cooling systems of the engine, heating, ventilation and air conditioning
+ Power supply system and production of the fulfilled gases
- Systems of electric equipment of the engine
   + Systems of ignition and engine management
   - Diagnostics of systems of electronic control and diagnostic equipment
      General information
      Application of an oscillograph for observation of signals in chains of control systems
      Diagnostics
   + Systems of a charge and start
+ Automatic transmission and interaxal differential
+ Transmission line
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ Schematic diagrams of electric connections


2598ff35



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

Digital multimeters perfectly are suitable for check of the electric chains which are in a static state, and also for fixing of slow changes of the traced parameters. When conducting the dynamic checks which are carried out on the working engine and also at identification of the reasons of periodic failures the oscillograph becomes absolutely irreplaceable tool.

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

The oscillograph allows to observe periodic signals and to measure characteristics of rectangular impulses, and also levels of slowly changing tension. The oscillograph can be used for:

  • Identifications of failures of unstable character;
  • Checks of results of the made corrections;
  • Activity monitoring lambda probe;
  • The analysis of the signals developed a lambda probe which deviation of parameters from norm is the unconditional evidence of violation of serviceability of functioning of a control system in general - on the other hand, correctness of a form of the impulses given a lambda probe can serve as a reliable guarantee of lack of violations in a control system.

Reliability and simplicity of operation of modern oscillographs do not demand from the operator of special special knowledge and experience. Interpretation of the obtained information can be easily made by elementary visual comparison of the oscillograms removed during check with the temporary dependences typical for various sensors and actuation mechanisms of automobile control systems given below.

Parameters of periodic signals

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

  • amplitude – a difference of the maximum and minimum tension (V) of a signal within the period;
  • the period – duration of a cycle of a signal (ms);
  • frequency – the number of cycles per second (Hz);
  • width – duration of a rectangular impulse (ms, microsec);
  • porosity – the repetition period relation to width (In foreign terminology the return is applied porosity the parameter called by a running cycle, expressed in %);
  • signal form – the sequence of rectangular impulses, single emissions, a sinusoid, sawtooth impulses, etc.
Characteristics of any signal

Usually characteristics of the faulty device strongly differ from reference that allows the operator easily and quickly visually to reveal the refused component.

Signals of a direct current - only signal tension is analyzed.

ECT sensor signal
TPS sensor
Lambda probe
MAF sensor

Signals of alternating current - are analyzed amplitude, frequency and a form of a signal.
 Sensor of detonations

Frequency-modulated signals - are analyzed amplitude, frequency, a form of a signal and width of periodic impulses.
Inductive CKP sensor
Inductive CMP sensor
 Inductive VSS sensor
RPM meters and provisions of shaft working at Hall's effect
Optical RPM meters and provisions of shaft
 Digital MAF and MAP sensors

The signals modulated on width of an impulse (ShIM) - are analyzed amplitude, frequency, a form of a signal and porosity of periodic impulses.
Fuel injector
Device of stabilization of turns of X/X (IAC)
 Primary winding of the coil of ignition
Ø/m EVAP system adsorber purge valve
EVAP system valves

The form of the signal given by an oscillograph depends on a set of various factors and can change considerably.

In a look told before starting replacement of the suspected component in case of discrepancy of a form of the removed diagnostic signal with the reference oscillogram, it is necessary to analyse carefully received result.

Digital signal
Analog signal

Tension

Zero level of a reference signal cannot be considered as absolute basic value, - "zero" real signal depending on concrete parameters of the checked chain can be shifted rather reference (see range 1 on an illustration the Digital signal) within a certain admissible range (see range 2 on an illustration the Digital signal and 1 on an illustration the Analog signal).

Full amplitude of a signal depends on the supply voltage of the checked contour and also can vary rather reference value in certain limits (see range 2 on an illustration the Digital signal and 2 on an illustration the Analog signal).

In chains of a direct current amplitude of a signal is limited to supply voltage. It is possible to give a chain of system of stabilization of turns of idling (IAC) which alarm tension does not change with change of turns of the engine in any way as an example.

In chains of alternating current signal amplitude already unambiguously depends on the frequency of work of a source of a signal, so, amplitude of the signal given by the sensor of provision of a bent shaft (CKP) will increase with increase in turns of the engine.

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

When checking the equipment of chains with Ý/m management (for example, the IAC system) at power off tension throws (see 4 on an illustration the Digital signal) can be observed which can be ignored quietly in the analysis of results of measurement.

It is not necessary to worry also at emergence of such deformations of the oscillogram as bevelling of the lower part of the forward front of rectangular impulses (see values 5 on an illustration the Digital signal) if, of course, the fact of a vypolazhivaniye of the front is not a sign of violation of serviceability of functioning of the checked component.

Frequency

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

The form of the removed signal can be edited and brought to a look, convenient for the analysis, by switching on an oscillograph of scale of temporary development of the image.

At observation of signals in chains of alternating current temporary development of an oscillograph depends on the signal source frequency (see range 3 on an illustration the Analog signal) determined by engine turns.

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

In certain cases characteristic changes of a signal are developed specularly rather reference dependences that is explained by reversibility of polarity of connection of the corresponding element and, in the absence of the ban on change of polarity of connection, can be ignored in the analysis.

Typical signals of components of control systems of the engine

Modern oscillographs are usually equipped with only two alarm wires together with a set of the various probes allowing to carry out connection of the device practically to any device.

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

Injectors

Control of composition of air-fuel mix in modern automobile electronic systems of injection of fuel is exercised by timely adjustment of duration of opening of electromagnetic valves of injectors.

Duration of stay of injectors abroach is defined by duration of the developed ECM of the electric impulses given on an entrance Ý/m valves. Duration of impulses usually does not exceed the limit of the range of 1 ÷ 14 ms.

The typical oscillogram of the impulse operating operation of an injector is submitted on the illustration Fuel Injector. Often on the oscillogram it is possible to observe also a series of the short pulsations following directly the initiating negative rectangular impulse and supporting Ý/m the valve of an injector abroach, and also the sharp positive throw of tension accompanying the moment of closing of the valve.

Serviceability of functioning of ECM can be easily checked by means of an oscillograph by visual observation of changes of a form of the operating signal at a variation of working parameters of the engine. So, duration of impulses at an engine provorachivaniye on single turns has to be slightly higher, than during the operation of the unit on low turns. Increase in turns of the engine has to be followed by corresponding increase in time of stay of injectors abroach. This dependence is especially well shown when opening a butterfly valve by short pressing the accelerator pedal.

 PERFORMANCE ORDER

  1. By means of the thin probe from the set attached to an oscillograph connect a red wire of the device to the injector ECM plug. Reliably ground the probe of the second alarm wire (black) oscillograph.
  2. Analyse a form of the signal engine which is read out during a provorachivaniya.
  3. Having started the engine, check a form of the operating signal on single turns.
  4. Having sharply pressed the accelerator pedal, lift the frequency of rotation of the engine to 3000 rpm, - duration of the operating impulses at the time of acceleration has to increase considerably, with the subsequent stabilization at the level, equal, or slightly smaller peculiar to idling turns.

Bystry closing of a butterfly valve has to lead to the oscillogram flattening confirming the fact of an overshoot of injectors (for systems with a fuel supply cut-off).

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

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

Typical dependence of duration of the operating impulses of opening of injectors on the working condition of the engine is presented in the table provided below.

Condition of the engine Duration of the operating impulse, ms
Single turns 1.5 ÷ 5
2000 + 3000 rpm 1.1 ÷ 3.5
Full gas 8.2 ÷ 3.5

Inductive sensors

 PERFORMANCE ORDER

  1. Start the engine and compare the oscillogram removed from an exit of the inductive sensor from reference.
Signal of the inductive sensor
  1. Increase in turns of the engine has to be followed by increase in amplitude of the pulse signal developed by the sensor.

Ø/m valve of stabilization of turns of idling (IAC)

In automotive industry electromagnetic IAC valves of a set of various types giving signals of also various form are used.

The common distinctive feature of all valves is the fact that porosity of a signal has to decrease with increase of the load of the engine connected with inclusion of the additional consumers of power causing decrease in turns of idling.

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

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

Step electric motor, reacting to the given ECM the pulsing operating signal, makes step correction of turns of idling of the engine according to the working temperature of cooling liquid and the current load of the engine.

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

 PERFORMANCE ORDER

  1. Warm up the engine up to the normal working temperature and leave it working at single turns.
  2. For increase in load of the engine include head headlights, the air conditioner, or, - on models with the power steering, - turn a steering wheel. Turns of idling have to fall for a short time, however right there again be stabilized due to operation of the IAC valve.
  3. Compare the removed oscillogram to the reference, given on the illustration Stabilization Device of turns X/X (IAC).

Lambda probe (oxygen sensor)

Oscillograms typical for the most often used on cars a lambda probes of zirconium type in which the basic tension of 0.5 Century is not used are provided in this subsection. Recently the increasing popularity is gained by titanic sensors which working range of a signal makes 0÷5 of V, and the high level of tension is given at combustion of the impoverished mix, low, - enriched.


 PERFORMANCE ORDER

  1. Connect an oscillograph between the plug a lambda probe on ECM and weight.
  2. Make sure that the engine is heated-up up to the normal working temperature.
  3. Compare the oscillogram displayed the measuring instrument with reference, given on the illustration Lambda probe (see above).
  4. If the removed signal is not wavy, and represents linear dependence, then, depending on tension level, it demonstrates excessive reimpoverishment (0 ÷ 0.15 In), or reenrichment (0.6 ÷ 1 V) of air-fuel mix.
  5. If on single turns of the engine the normal wavy signal takes place, try to squeeze out several times sharply gas loops, - fluctuations of a signal should not exceed the limit of the range of 0 ÷ 1 Century.
  6. Increase in turns of the engine has to be followed by increase in amplitude of a signal, reduction - decrease.

Sensor of a detonation (KS)

 PERFORMANCE ORDER

  1. Connect an oscillograph between the plug of the sensor of a detonation of ECM and weight.
  2. Make sure that the engine is heated-up up to the normal working temperature.
  3. Sharply squeeze out the accelerator pedal and compare a form of the removed signal of alternating current with reference, given on the illustration Sensor of Detonations (see above).
  4. At insufficient image sharpness slightly knock on the block of cylinders around placement of the sensor of a detonation.
  5. If it is not possible to achieve unambiguity of a form of a signal, replace the sensor, or check a condition of an electrical wiring of its chain.

Ignition signal at the exit of the amplifier of ignition

 PERFORMANCE ORDER

  1. Connect an oscillograph between the plug of the amplifier of ignition of ECM and weight.
  2. Warm up the engine up to the normal working temperature and leave it working at single turns.
  3. The sequence of rectangular impulses of a direct current has to be given for the screen of an oscillograph. Compare a form of the accepted signal to reference, paying close attention to coincidence of such parameters as amplitude, the frequency and a form of impulses.
The operating signal of the amplifier of ignition
  1. At increase in turns of the engine the frequency of a signal has to increase in direct ratio.

Primary winding of the coil of ignition

 PERFORMANCE ORDER

  1. Connect an oscillograph between the plug of the coil of ignition of ECM and weight.
  2. Warm up the engine up to the normal working temperature and leave it working at single turns.
  3. Compare a form of the accepted signal from the reference, given on an illustration Primary winding ignition coil (see above), - positive throws of tension have to have constant amplitude.
  4. Unevenness of throws can be caused by the excessive resistance of a secondary winding, and also malfunction of VV of a wire of the coil.

Contacts

Color of wires

Check conditions

Tension, In

Engine

<—> E 9 (E 8-17)

<—>B-Y BR

Always

9 ÷ 14

+ B<—> (E 5-16) E 9 (E 8-17)

<—>B-R BR

Ignition is included

9 ÷; 14

VC (E 8-2)<—> of E 8 (E 8-18)

<—>Y-B BR

Ignition is included

4.5 ÷ 5.5

VTA 1<—> (E 8-23) E 8 (E 8-18)

<—>L-W BR

Ignition is included, the butterfly valve is completely closed//is open

0.3 ÷ 1.0 / 2.7 ÷ 5.2 5.2

VG (E8-10)<—> of E8G (E8-19)

<—>Y-R G-B

Idling, To/in is switched off

1.1-1.5

VV1 +<—> (E9-10) NE-(E8-24)

<—>O W

Idling

Generation of impulses

VV 2+ (E 9-22)<—> NE - (E 8-24)

<—>L W

Idling

Generation of impulses

NE + (E 8-16)<—> of NE - (E 8-24)

<—>B W

Idling

Generation of impulses

<—>OC 1+ (E 9-6) OC 1-(E 9-5)

<—>Y-B G-W

Ignition is included

Generation of impulses

OC2 +<—> (E9-29) OC2-(E9-18)

GR<—> of G-Y

Ignition is included

Generation of impulses

THA (E8-22)<—> of E8 (E8-18)

<—>L-B BR

Idling, temperature of the soaked-up air 20 a hail.

0.5 ÷ 3.4

THW (E8-14)<—> of E8 (E8-18)

<—>G-W BR

Idling, OZh 80 temperature hail.

0.2 ÷ 1.0

STA (E5-7)<—> of E9 (E8-17)

<—>B BR

Provorachivaniye

Not less than 6.0

#10<—> (E8-5) E01 (E9-21)

#20<—> (E8-6) E01 (E9-21)

#30(E9-1)<—> E01 (E9-21)

#40<—> (E9-2) E01 (E9-21)

#50<—> (E9-3) E01 (E9-21)

#60<—> (E9-4) E01 (E9-21)

<—>W WB

<—>Y WB

<—>B WB

L<—> WB

<—>R WB

<—>G WB

Ignition is included

9 ÷ 14

Idling

Generation of impulses

IGT 1<—> (E 9-11) E 9 (E 8-17)

<—>B-Y BR

Idling

Generation of impulses

<—>IGT2 (E9-12) E9 (E8-17)

<—>L-R BR

<—>IGT3 (E9-13) E9 (E8-17)

<—>Y-G BR

<—>IGT4 (E9-14) E9 (E8-17)

<—>L-Y BR

<—>IGT5 (E9-15) E9 (E8-17)

<—>Y BR

<—>IGT6 (E9-16) E9 (E8-17)

<—>G-B BR

IGF (E-25)<—> of E9 (E8-17)

<—>B BR

Ignition is included

4.5 ÷ 5.5

Idling

Generation of impulses

ACIS (E9-17)<—> of E01 (E9-21)

<—>R-Y W-B

Ignition is included

9 ÷ 14

FC (E 5-3)<—> of E 01 (E 9-21)

<—>L-Y W-B

Ignition is included

9 ÷; 14

Idling

0 ÷ 3.0

RSO (E9-26)<—> of E01 (E9-21)

<—>Y-R W-B

Ignition is included, the E 9 ECM socket is disconnected

9 ÷ 14

OXS (E6-8)<—> of E9 (E8-17)

<—>W BR

Maintenance of 2500 rpm within 3 min. after warming up of the engine

Generation of impulses

HTS (E 6-9)<—> of E 03 (E 9-30)

<—>B W-B

Idling

Lower than 3.0

Ignition is included

9 ÷ 14

KNKR (E 9-27)<—> of E 9 (E 8-17)

<—>W BR

Idling

Generation of impulses

KNKL (E 9-28)<—> of E 9 (E 8-17)

<—>B BR

NSW (E6-20)<—> of E9 (E8-17)

<—>B-W BR

Ignition is included, the AT mode other than "P" or "N" is chosen

9 ÷ 14

Ignition is included, AT in the "P" or "N" mode

0 ÷ 3.0

SPD (E6-22)<—> of E9 (E8-17)

<—>V-W BR

Ignition is included, slow rotation of a driving disk

0 ÷ 5

TC (E5-5)<—> of E9 (E8-17)

<—>P-B BR

Ignition is included

9 ÷ 14

W<—> (E 6-6) E 9 (E 8-17)

<—>Y-G BR

Ignition is included

Lower than 3.0

<—>EVP1 (E8-7) E01 (E9-21)

<—>W-L W-B

Ignition is included

9 ÷ 14

CCV<—> (E 5-10) E 01 (E 9-21)

<—>G W-B

Ignition is included

9 ÷ 14


Contacts

Color of wires

Check conditions

Tension, In

PS (E8-9)<—> of E9 (E8-17)

<—>B-Y BR

Ignition is included

9 ÷14

CF (E 6-26)<—> of E 9 (E 8-17)

<—>R-W BR

The fan works at high speed

9 ÷ 14

The fan works at low speed or is switched off

0 ÷ 2

TACH (E6-27)<—> of E9 (E8-17)

<—>O BR

Idling

Generation of impulses

TBP (E 6-3)<—> of E 01 (E 9-21)

<—>L-R W-B

Ignition is included, the vacuum hose is disconnected from VSV of pressure of vapors of fuel

9 ÷ 14

PTNK (E5-17)<—> of E9 (E8-17)

<—>L-O BR

Ignition is included

2.9 ÷ 3.7

Ignition is included, vacuum of 30 mm of mercury is created.

No more than 0.5

SIL (E 5-4)<—> of E 9 (E 5-17)

<—>W BR

In the course of transfer

Generation of impulses

STP (E 5-15)<—> of E 9 (E 8-17)

<—>G-O BR

Ignition is included, the brake pedal is squeezed out

7.5 ÷ 14

Ignition is included, the pedal of a brake is released

Lower than 1.5

AFR +<—> (E 8-11) E 9 (E 8-17)

<—>R BR

Ignition is included

3.0 ÷ 3.6

AFL+ (E5-12)<—> of E9 (E8-17)

L<—> BR

AFR -<—> (E8-20) E9 (E8-17)

<—>G B R

Ignition is included

2.7 ÷ 3.3

AFL-(E8-21) - E9 (E8-17)

<—>B-W BR

HAFR (E8-3)<—> E04(E8-1)

HAFL (E8-4)<—> of E05 (E8-8)

L<—> W-B

Idling

Lower than 3.0

<—>G W-B

Ignition is included

9 ÷ 14

KSW (E6-23)<—> of E9 (E8-17)

<—>L-B BR

In installation time of a key in the ignition lock

Lower than 1.5

Key not in the ignition lock

4 ÷ 5

RXCK (E6-19)<—> of E9 (E8-17)

<—>P BR

In installation time of a key in the ignition lock

Generation of impulses

CODE (E6-28)<—> of E9 (E8-17)

V<—> BR

In installation time of a key in the ignition lock

Generation of impulses

IGSW (E5-2)<—> of E9 (E8-17)

<—>B-O BR

Ignition is included

9 ÷ 14

TXCT (E6-18)<—> of E9 (E8-17)

<—>GR BR

In installation time of a key in the ignition lock

Generation of impulses

IMLD (E5-22)<—> of E9 (E8-17)

L<—> BR

Key not in the ignition lock

Generation of impulses

MREL (E5-8)<—> of E9 (E8-17)

<—>B-W BR

Ignition is included

9 ÷ 14

Automatic transmission

SL1 +<—> (E9-20) SL1-(E9-19)

<—>L-B L-W

Ignition is included

10 ÷ 14

1st or 2nd transfer

10 ÷ 14

The 3rd or O/D transfer

Lower than 1

SL2 +<—> (E9-9) SL2-(E9-8)

<—>R-B R-W

Ignition is included

Lower than 1

1st or 2nd transfer

10 ÷ 14

The 3rd or O/D transfer

Lower than 1

DSL (E9-7)<—> weight

R - L<—> mass of a body

Ignition is included

Lower than 1

The movement in the blocked situation

10 ÷ 14

NC+ (E9-24)<—> of NC-(E9-23)

<—>R G

The working engine

Pulse signal

Lower than 1<—> 4 ÷ 5

NT + (E7-5)<—> OF NT-(E7-CH)

L<—> LG

The working engine

Pulse signal

Lower than 1<—> 4 ÷ 5

SLT +<—> (E7-3) SLT - (E7-2)

<—>G-B G

Ignition is included

10 ÷ 14

<—>OD1 (E6-24) E1 (E8-17)

<—>Y-G BR

Ignition is included

5 ÷ 6

L<—> (E7-13) E1 (E8-17)

<—>L-R BR

Ignition is included and the AT mode "L" is chosen

10 ÷ 14

Ignition is included and the AT mode, other than "L" is chosen

Lower than 1

2 (E7-14)<—> E1 (E8-17)

<—>G-Y BR

Ignition is included and the mode "2" AT is chosen

10 ÷ 14

Ignition is included and the AT mode, excellent from "2" is chosen

Lower than 1

<—>R (E7-8) E1 (E8-17)

<—>R-B BR

Ignition is included and the "R" AT mode is chosen

10 ÷ 14

Ignition is included and the AT mode other than "R" is chosen

Lower than 1

D<—> (E7-16) E1 (E8-17)

GR<—> of BR

Ignition is included and the AT mode "D" is chosen

10 ÷ 14

Ignition is included and the AT mode, other than "D" is chosen

Lower than 1

<—>N (E7-7) E1 (E8-17)

<—>R-W BR

Ignition is included and the "N" AT mode is chosen

10 ÷ 14

Ignition is included and the AT mode other than "N" is chosen

Lower than 1

<—>P (E7-9) E1 (E8-17)

<—>G-W BR

Ignition is included and the "P" AT mode is chosen

10 ÷ 14

Ignition is included and the AT mode other than "P" is chosen

Lower than 1

ODLP (E5-9)<—> of E1 (E8-17)

<—>R-W BR

Ignition is included, burns To/L switching off of the O/D mode

Lower than 1

Ignition is included, To/L switching off of the O/D mode does not burn

10 ÷ 14

<—>ODMS (E7-12) E 1 (E8-17)

GR-L<—> of BR

Ignition is included

10 ÷ 14

Ignition is included and the switch of the O/D mode keeps

Lower than 1