Jeep Grand Cherokee

1993-1999 of release

Repair and operation of the car

Jeep Grand Cherokee
+ Cars of the Jeep Grand Cherokee brand
+ Settings and routine maintenance
+ Line six-cylinder engine
+ V8 engine
+ Procedures of the general and capital repairs of the engine
+ Cooling systems, heating and air conditioning
+ A power supply system and production of the fulfilled gases
+ System of electric equipment of the engine
- Systems of decrease in toxicity of the fulfilled gases and engine management
   General information
   System of multiposition injection of fuel (MPFI) and information sensors - the description
   Removal and installation of the electronic module of management (RSM)
   Description of the principle of action of system of self-diagnostics and procedure of reading of codes of malfunctions
   Information sensors
   System of the operated ventilation of a case (PCV)
   System of recirculation of the fulfilled gases (EGR)
   System of catching of vapors of fuel (EVAP)
   Catalytic converter
+ Manual box of gear shifting
+ Automatic transmission
+ Transfer case
+ Coupling and transmission line
+ Brake system
+ Suspension bracket and steering
+ Body
+ System of onboard electric equipment
+ Governing bodies and methods of operation

Description of the principle of action of system of self-diagnostics and procedure of reading of codes of malfunctions

Before starting a conclusion of codes of malfunctions carefully check a condition of all electric sockets and hoses. Make sure of reliability of fastening of sockets, lack of traces of corrosion and pollution; hoses also have to be in satisfactory condition (without cracks and cuts) and to be reliably fixed on the unions.

On models to which this manual is devoted control CHECK ENGINE (Check the engine) or MIL (Indication of refusals) is located on an instrument guard and at start of the engine flashes for three seconds as check of serviceability of a lamp. In case of problems in the MPFI system the lamp lights up and remains included.

Access to RSM of information on the recorded system failures which is stored in memory is possible with the help of either the ignition key, or the special reader of the diagnostic DRB II codes. This device is connected to diagnostics socket located in a motive compartment. At the same time codes and parameters of malfunctions are displayed the display of the reader. However the DRB II scanner is quite expensive device and most of amateur mechanics prefer to use of it an alternative method. A negative side of a method of reading of codes of malfunctions by means of the ignition key is lack of a possibility of highlighting of the complete list of codes. The majority of problems decide usually or diagnosed rather easily and if it is not possible to obtain certain information, it is necessary to ask for the help in a workshop of dealer office or car service at the disposal of which there is necessary more difficult equipment.


  1. For highlighting of codes of malfunctions by means of the ignition key first of all cock the parking brake and transfer transmission to situation "P". Lift the frequency of rotation of the engine to 2500 rpm, then slowly dump turns to single. For a short time turn on (then switch off) the air conditioning system. Then, having squeezed out a foot brake, consistently carry out the selector lever through all provisions (Reverse, Drive, Low, etc.), having finished on situation "P" again (Park - the Parking). It will allow the processor of the module to record codes of all refusals connected with the sensors reacting to changes in functioning of transmission, the engine (its turns) and the air conditioner.
  2. For highlighting of codes of malfunctions a lamp of CHECK ENGINE or MIL, consistently turn the ignition key in provisions of ON, OFF, ON, OFF and again - ON (the engine is killed). After that the lamp will begin to highlight the codes recorded in memory by RSM. At first the lamp will highlight the first figure of a two-digit code, then, after a pause - the second. For example: the code 23 (an air temperature sensor contour) will look as follows: two flashes, pause, three flashes.
  3. For input of a code of malfunction in memory of the control unit of the engine certain conditions have to be satisfied. It can be a preset value of turns of the engine, its temperature or tension (entrance) signal coming to the controller. There is a probability that at poll any of system contours the code of the refusal taking in it place will not be entered into memory. It can result from lack of one of criteria of a code of this malfunction (non-performance of one of conditions). For example: for adequate poll (regarding detection of malfunctions) the MAR sensor contour the engine has to function with a rotation frequency within (750 - 2000) rpm. If the frequency of the engine exceeds 2400 rpm, the output signal of the MAR sensor will be short-circuited on weight that will not allow to enter a refusal code into memory of the controller. Also absolutely opposite situation can take place: in memory the malfunction code absolutely of other component of system will be brought. For example: problems with pressure of fuel cannot be registered by the processor directly, however, they lead to reimpoverishment or reenrichment of air-fuel mix that forces system of self-diagnostics to bring in memory of the module a refusal code in a contour of the oxygen sensor. It is necessary to remember constantly mutual crossing of coverages of various sensors and contours, and also influence at each other of results of functioning of power supply systems and control of toxicity of the fulfilled gases.

The table brought below to attention readers represents the list of codes of possible malfunctions and refusals of functioning of system which can be highlighted during performing its diagnostics. Besides, are listed in the table possible each of alleged refusals. If after the introduction of all corrections made on the basis of results of this diagnostics a situation does not return to normal, it is necessary to address for consultation in a workshop of dealer office or car service.

Codes of diagnostics of malfunctions

Not all from the given codes can take place on all models.

Code 11 At rotation of the engine the basic signal from the distributor does not arrive. Check a contour between the distributor and RSM.
Code 12 Problem with contacts of the battery. Direct giving of power supply from the battery on the controller was absent during not less than 50 inclusions of ignition.
Code 13 ** Points to problems with pneumatic (vacuum) system of the MAR sensor.
Code 14 ** Tension of the MAR sensor is not enough or too highly.
Code 15 ** Problems with VSS signals. Signals of the sensor are not defined at the movement of the car.
Code 16 Loss of power supply from the battery.
Code 17 The engine too long remains cold. The sensor of temperature of a cooler fixes temperature below the normal worker during functioning of the engine (check the thermostat)
Code 21 ** Problems in a contour of the O 2 sensor. There are no fluctuations of tension of the sensor on the processor.
Code 22 ** It is not enough or too highly cooler sensor tension. Check the sensor.
Code 23 ** Speaks about too low (below admissible value) or too high (above admissible) the level of an entrance signal of the sensor of air temperature.
Code 24 ** It is not enough or too highly TPS tension. Check the sensor.
Code 25 ** IAC motor contour. Short circuit in one or more contours of the motor takes place.
Code 27 One of contours of management of injectors does not react properly to signals of management. Check contours.
Code 31 ** Problem in a contour an electromagnet of a purge of a coal adsorber.
Code 32 ** The break or short circuit in a contour of an electromagnet of EGR is recorded it is possible during diagnostics the imbalance of composition of air-fuel mix was not revealed.
Code 33 Air conditioner clutch coupling relay contour. The break or short circuit in a relay contour is defined.
Code 34 The break or short circuit in contours of electromagnets of vacuum control of turns or ventilation is defined.
Code 37 Contour of an electromagnet of coupling of the converter of rotation. The break or short circuit in a contour of an electromagnet of disconnection of a part of a throttle of the converter of rotation takes place (only AT).
Code 41 ** Problems in system of a charge. Arise when battery tension from the ASD relay falls lower than 11.75 Century.
Code 42 The break or short circuit of a contour of management of the ASD relay is revealed.
Code 44 Wrong tension of the sensor of temperature of the battery. Problems with a battery temperature tension contour in RSM.
Code 45 Electromagnet of the transfer to the raising transfer. Problems in an electromagnet contour are revealed.
Code 46 ** Tension of system of a charge is too high. The processor informs on inadequate adjustment of tension of the battery.
Code 47 ** Tension of system of a charge is not enough. During functioning of the engine the measured entrance tension of the battery is lower than the set charge voltage and during active check of an output signal of the generator noticeable changes of tension were not revealed.
Code 51 * The output signal of the O 2 sensor demonstrates reimpoverishment of gas mixture during functioning of the engine.
Code 52 ** The output signal of the O 2 sensor demonstrates reenrichment of gas mixture during functioning of the engine.
Code 53 Internal malfunction of the RSM module.
Code 54 There is no signal of the sensor of position of the camshaft from the distributor. Problems with a contour of synchronization of the distributor.
Code 55 Completion of process of reading of codes of malfunction control lamp of CHECK ENGINE. Code of end of the mode of diagnostics.
Code 62 Unsuccessful attempt to correct indications of a run of EMR in memory of the monitor.
Code 63 Failure of the monitor. Denial of record in memory. Check RSM.

** These codes are highlighted by CHECK ENGINE lamp on an instrument guard during the operation of the engine in the course of record of a code of malfunction.