Toyota Land Cruiser 100/Amazon, Lexus LX 470

since 1997 release

Repair and operation of the car


Toyota Land Cruiser, Amazon, Lexus LX470
+ Identification numbers of the car
+ Governing bodies and methods of safe operation of the car
+ Settings and routine maintenance of the car
+ Engine
+ Cooling systems of the engine, heating of salon and air conditioning
+ A power supply system and production of the fulfilled gases
+ Engine electric equipment
- Control systems of the engine and decrease in toxicity of the fulfilled gases
   Specifications
   System of onboard diagnostics (OBD) - the principle of functioning and codes of malfunctions
   Application of an oscillograph for observation of working signals of a control system
   Check of a state and replacement of ESM
   Information sensors - the general information and check of serviceability of functioning
   Replacement of information sensors
   System of catching of fuel evaporations (EVAP) - the general information, check of a state and replacement of components
   System of the operated ventilation of a case (PCV)
   The catalytic converter - the general information, check of a state and replacement
+ Gear shifting box
+ Transmission line
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment


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Information sensors – the general information and check of serviceability of functioning

In order to avoid failure of ESM when performing of the checks described below use only the digital voltmeter with high (over 10 megohms) an impedance!


The car equipped with the OBD-II system should be driven away on car repair shop for reading of codes of malfunctions with use of the special scanner. There are some checks (connected with identification of causes of failures at start of the engine) which the owner of the vehicle can independently execute, in all other cases the car should be driven away in car service.

2-contact thermistors (sensors of temperature of cooling liquid, the soaked-up air, etc.)

Thermistors represent the resistors changing resistance depending on temperature, and developing the corresponding alarm tension. Sensors of temperature of cooling liquid of the engine (EST) and temperature of the soaked-up air (IAT) belong to elements of this kind. It should be noted that resistance of these sensors changes in inverse proportion to change of temperature, i.e., DECREASES with INCREASE of the last and vice versa. For check of termistorny sensors switch a multimeter to measurement of resistance, disconnect an electrical wiring from the sensor and measure resistance between assembly plugs. Take temperature. Then warm up the sensor up to the certain temperature and again measure its resistance. Compare the received results to ordered. Location of the ECT sensor is shown on an illustration below. The IAT sensor is built in the MAF sensor. For the IAT sensor resistance between the MAF sensor E2 and THA plugs is measured.

Schedule of dependence of resistance of ECT and IAT sensors on temperature

Components of installation of the ECT sensor

Further it is necessary to check correctness of the basic tension given on the sensor by the processor. Connect an electrical wiring to the sensor, switch a multimeter to voltage measurement and connect its probes to electrical wiring plait plugs on the socket. The nominal rate of basic tension has to make about 5.0 Century. Check is made at the included ignition, do not start the engine. If violation of serviceability of giving on the sensor of basic tension takes place, it is necessary to check a condition of a connecting electrical wiring and actually ESM.

Potentiometers (sensor of provision of a butterfly valve)

The potentiometer represents the resistor which resistance changes as a result of mechanical movement of some components. The TPS sensor develops the alarm tension proportional to the current size of resistance of a potentiometer determined by the provision of a butterfly valve in the throttle case. The signal from the sensor arrives on ESM which on the basis of the analysis of the arriving data defines situation and the direction of the movement of the gate. For check of serviceability of functioning of the TPS sensor the nature of change of size of resistance of a potentiometer depending on extent of opening of a butterfly valve is quantitatively estimated. This contour is defined as VTA – E2.

 PERFORMANCE ORDER

1. Disconnect an electrical wiring from TPS. On models of the corresponding complete set disconnect the vacuum line and by means of the manual vacuum pump create depression on the device of positioning of a butterfly valve. By means of an ohmmeter measure resistance between the TPS sensor VTA and E2 plugs (address an accompanying illustration). At completely closed gate resistance has to be ranging from 0.2 to 5.7 kOhm, and at completely open – the ohmmeter has to show infinity.
2. Further it is necessary to check correctness of the basic tension given on the sensor by the processor. Connect an electrical wiring to the sensor, switch a multimeter to voltage measurement and connect its probes to the corresponding plugs of a plait of an electrical wiring on the socket. Tension on sensor conclusions with opening of a butterfly valve has to increase: at completely closed gate it to be within 0.7 B, and at completely open – 2.7 – 5.2 Century. If violation of serviceability of giving on the sensor of basic tension takes place, it is necessary to check a condition of a connecting electrical wiring and actually ESM.

2-contact electromagnetic sensors (sensors of provision of cranked and distributive shaft and sensor of speed of the movement of the car)

In a basis of a design of electromagnetic sensors the permanent magnet placed in a wire winding is put. Typical representatives of electromagnetic sensors are sensors of provision of cranked and distributive shaft (ICR and CMP), and also the sensor of speed of the movement of the car (VSS). The steel disk fixed on a gear wheel is equipped with the uvulas passing between the polar terminations of a magnet and causing short circuit of magnetic field. Fluctuations of magnetic field lead to change of alarm tension of the sensor. On the basis of the analysis of the signals of ESM arriving from sensors determines the speed of the movement of the car (VSS), or the current provision of the corresponding shaft (ICR and CMP). The CKP sensor develops G signal for ECU. The arrangement and schemes of check of sensors are shown on illustrations below.

Components of installation and check of the CMP sensor

Check of the CKP sensor

Location of the CKP sensor

Location of the VSS sensor


 PERFORMANCE ORDER

For check of CKP and CMP sensors measure resistance between plugs of their sockets. On the cold engine (temperature is lower the 53rd hail.) on the CMP sensor resistance has to be 835 – 1400 Ohms, and on the CKP sensor: 1630 – 1740 Ohms. On the heated-up engine (temperature 53 – 100 hail.) on the CMP sensor resistance has to be 1060 – 1645 Ohms, and on the CKP sensor – 2065 – 3225 Ohms. In case of VSS transmission needs to be given previously to neutral situation, then, holding one wheel not movably, to rotate manually opposite (use the help of the assistant), it is necessary to simulate the speed of the movement about 3.5 km/h, watch indications of the measuring instrument. This check can be made also on the sensor removed from the car, – it is necessary to rotate a driving gear wheel of assembly.

On some models VSS without driving gear wheel is used, such sensors have to be checked by in situ (without removal from the car). When checking the sensor of ICR the help of the assistant who will have to turn the engine a starter short breakthroughs is also required, you monitor indications of the voltmeter which has to register the weak uniform fluctuations confirming serviceability of a state and functioning of a magnetic part of the sensor.

Lambda probes

O 2 sensors, or lambda probes trace percentage of oxygen in the fulfilled engine gases. The molecules O 2 which are present at system of release, reacting with a sensitive element of the sensor, force the last to develop alarm tension. Signal amplitude, depending on concentration of oxygen can make from 0.1 B (high content O 2, the grown poor air-fuel mix) to 0.9 B (low contents O 2, the enriched mix). ESM continuously traces the signal arriving from a lambda probe, and on the basis of the arriving data makes the corresponding correction of structure of air-fuel, trying to support him at optimum level (14.7 parts of air on 1 part of fuel, – stoichiometric number). Correction of composition of mix is made due to management of duration of time of opening of injectors. The lambda probe begins to develop alarm tension only after it is heated-up up to the normal working temperature making about 320 °C. In a look told, in the course of warming up of the ESM engine works in the mode of the opened contour. Do not forget to check serviceability of a state of all being a part of system a lambda probes.

 PERFORMANCE ORDER

Access to a lambda probes is usually complicated. Be careful, you remember that components of system of release can remain hot during even long time after a stop of the engine and pressing to their surface of plaits of an electrical wiring can lead to destruction of their isolation. Try to make, whenever possible, check of components of system with use of the scanner connected to the DLC socket, the device allows to reveal changes of alarm tension of each of a lambda probes within thousand shares of volt.

1. Check the millivoltny output signal developed by the sensor. Find the socket of an electrical wiring and from its reverse side accurately connect voltmeter probes to the corresponding contact plugs. On the majority of models the positive probe is connected to the alarm plug of the socket of the sensor (SIGNAL), and negative – a grounding lemma (see. Onboard electric equipment).

Fluctuations of alarm tension nizhnepotochny the lambda probes occurs much more slowly than at verkhnepotochny that is explained by result of operation of the catalytic converter transforming the carbon monoxides which are present at composition of the fulfilled gases, hydrocarbons and oxides of nitrogen to nontoxical carbon dioxide and water which oxygen in much smaller degree reacts with a sensitive element of the sensor.

2. At the cold engine, in the mode of the opened contour, the lambda probe develops a steady amplitude signal in the range of 0.1 - 0.2 V. After passing about two minutes the sensor leaves in operating temperature condition and amplitude of its alarm tension begins to fluctuate in the range from 0.4 to 0.6 V, depending on the content of oxygen in the fulfilled gases. If the sensor leaves in an operating mode too slowly, or does not leave at all, and also at stabilization of tension in the middle of the working range of tension, the sensor should be replaced. If tension at the exit of the sensor was stabilized near one of limits of the specified range probably of ECM is not able to compensate mechanical malfunctions of the engine, such as suction of air or "pouring" injectors.

Do not forget that nizhnepotochny the lambda probe works much more slowly verkhnepotochny (see below).

3. Pull together a vacuum hose which is behind a butterfly valve. Tension has to fall approximately till 0:12 In (still quickly changing). It checks ability of the sensor to distinguish mix reimpoverishment. Attach a hose on the place.


4. Enrich mix, giving to an inlet path by means of the propane gun gas. Tension has to increase approximately to 0.9 B (still quickly changing). It checks ability of the sensor to distinguish mix reenrichment.
5. If the output tension of the sensor is higher or lower than the specified limits, the sensor or its conducting is faulty. Check integrity of conducting and if it is necessary, repeat check.
6. Check also serviceability of functioning of a chain of the heater a lambda probe. Disconnect an electrical wiring from the sensor and connect an ohmmeter to contact plugs + In (+) and NT (-) of the socket from the sensor (address an accompanying illustration). Compare result of measurements to requirements of Specifications. Remember that verkhnepotochny and nizhnepotochny sensors are not interchangeable. Further it is necessary to check serviceability of giving of food in a sensor heater chain, – disconnect an electrical wiring and connect the voltmeter to the socket from a plait: at the included ignition (the engine do not start) on plugs of the socket battery tension has to take place. In case of need check a condition of a chain on the site between the sensor and the safety lock/main thing of the relay. The faulty sensor replace (see schemes of electric connections Onboard electric equipment at the end).

Sensor of measurement of mass of an air stream

The sensor serves for measurement of an expense of the air throttle which is soaked up in the case. ESM uses information arriving from the sensor for adjustment of duration of time of opening of injectors, – the more air is soaked up in the engine (acceleration), the last needs bigger amount of fuel. On the considered models sensors of an air stream of vortex type with a sensitive element on the basis of incandescence thread are used. The device allows to define a weight expense of a stream and received the name of the sensor of mass of air (MAF). On the basis of information of ESM arriving from the sensor makes timely correction of composition of air-fuel mix.

On the models considered in the present manual MAF sensors of 5-contact type are used. For them remove an inlet air duct and include ignition. Connect the positive probe of the voltmeter to VG contact, and negative – to contact of E3 (address an accompanying illustration). Blow in the sensor and make sure of change of tension.

Detonation sensors

On the petrol V8 models two sensors of a detonation, on one on each of heads of cylinders are used (under the inlet pipeline).

Sensors of a detonation elicit the fact of increase in intensity of the vibrations of the engine arising at a detonation of air-fuel mix and give the relevant information allowing ESM on the module of management to make in due time the reduction of a corner of an advancing of ignition suppressing a detonation.

 PERFORMANCE ORDER

For check of serviceability of a condition of the sensor of a detonation disconnect from it an electrical wiring and measure resistance between the contact plug of the socket and mass of the case of assembly, conductivity has to be absent (address an accompanying illustration). Replace the faulty sensor.

The sensor switch of permission of start (model with AT)

The sensor switch of permission of start is installed behind on a transmission dome, in its top part and serves for the notice of ESM on the fact of finding of AT in provisions "P" and "N". This information is used by the processor at management of functioning of system of stabilization of turns of idling.

In order to avoid violation of stability of turns of idling do not begin the movement at the disconnected sensor switch of permission of start.

More detailed information on the principle of functioning of the sensor switch of permission of start is stated in the Head Korobka of gear shifting.

Sensor of pressure of vapors of fuel

The sensor serves for tracking of pressure/depth of depression in the fuel tank. On the basis of information of ESM arriving from the sensor in due time elicits the fact of violation of serviceability of a purge of a coal adsorber of the EVAP system and brings the corresponding diagnostic code in memory of OBD-II. Performance of work on restoration of serviceability of functioning of the EVAP system should be charged to specialists of car service.