Toyota Corolla

1992-1998 of release

Repair and operation of the car

Toyota Corolla
+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engines
+ 4. Cooling systems, heating
+ 5. Fuel, exhaust systems
- 6. System of decrease in toxicity
   6.1. Specifications
   6.2. Electronic control system
   6.3. Electronic control unit
   - 6.4. System of onboard diagnostics
      6.4.1. Reading of diagnostic codes
   + 6.5. Sensors of system of automatic control of the engine
   6.6. System of catching of vapors of gasoline
   6.7. System of recirculation (EGR system)
   6.8. System of compulsory ventilation of a case (PCV system)
   6.9. Catalytic converter
+ 7. Transmissions
+ 8. Coupling and half shafts
+ 9. Brake system
+ 10. Suspension bracket and steering
+ 11. Body
+ 12. Electric equipment


6.4. System of onboard diagnostics



This procedure of reading of codes does not belong to release cars since 1996 which are equipped with the OBD-II system. Diagnosing of these cars requires the special scanner which is reading out various levels of the coded information. In case of refusal the on-board computer, cars are subject to diagnostics in service of car service of the dealer or in a specialized workshop.

The system of self-diagnostics which finds and defines refusals in all network is built in an electronic control unit. At failure detection the following occurs the control unit: the light index of CHECK-ENGINE ("check the engine") lights up, the type of malfunction is identified, diagnostic codes register and brought in memory. The electronic control unit stores the codes of malfunctions assigned for a concrete type of refusal. These codes are cancelled when changing a safety lock of system of electronic injection of fuel at the switched-off ignition.

The light index of CHECK-ENGINE ("check the engine") located on the dashboard lights up at turn of the ignition key, is in position of ON (the engine does not work). After start of the engine, the lamp has to go out. If the lamp of the index does not die away, then it means that the system of self-diagnostics found some refusal.