Diagnosis; Fail-Safe - Toyota 1NZ-FE User Manual

12. Diagnosis

D When the ECM detects a malfunction, the ECM makes a diagnosis and memorizes the failed section.
Furthermore, the MIL (Malfunction Indicator Lamp) in the combination meter illuminates or blinks to
inform the driver.
D The ECM will also store the DTCs of the malfunctions.
D The DTCs can be accessed by the use of the hand-held tester.
D To comply with the OBD-II regulations, all the DTCs (Diagnostic Trouble Codes) have been made to
correspond to the SAE controller codes. Some of the DTCs have been further divided into smaller
detection areas than in the past, and new DTCs have been assigned to them. For details, refer to the 2006
Yaris Repair Manual (Pub. No. RM00R0U).
Service Tip
To clear the DTC that is stored in the ECM, use a hand-held tester or disconnect the battery terminal
or remove the EFI fuse for 1 minute or longer.

13. Fail-Safe

When a malfunction is detected at any of the sensors, there is a possibility of an engine or other malfunction
occurring if the ECM were to continue to control the engine control system in the normal way. To prevent
such a problem, the fail-safe function of the ECM either relies on the data stored in memory to allow the
engine control system to continue operating, or stops the engine if a hazard is anticipated. For details, refer
to the 2006 Yaris Repair Manual (Pub. No. RM00R0U).
ENGINE - 1NZ-FE ENGINE
EG-59