The «Check engine» indicator (Honda Accord 3)

The "CHECK ENGINE" lamp on the instrument cluster is checked by the ECU every time the ignition key is turned to the "ON" position. The lamp should light for 2 seconds and then go out. In a normal situation, the lamp does not remain lit while the engine is running.

If the warning lamp illuminates while the engine is running, the ECU has detected a system fault. The fault may be either a signal loss or a signal out of range, too large or too small. Additionally, when the lamp illuminates, the ECU uses a default value or failsafe mode, in which preset values replace the faulty or missing signal.

If the Accord or Prelude service connector is connected during diagnosis, the CHECK ENGINE light will illuminate even if there is no fault. When the repair or diagnosis is complete, the memory should be checked for any stored codes and cleared if necessary.