Sequoia SR5 4WD V8-4.7L (2UZ-FE) (2001)
Malfunction Indicator Lamp: Description and Operation
Malfunction Indicator Lamp (MIL)
OBD II regulations require that the vehicle's on-board computer lights up the Malfunction Indicator Lamp (MIL) on the instrument panel when the
computer detects a malfunction in the emission control system/components or in the powertrain control components which affect vehicle emissions, or a
malfunction in the computer. In addition to the MIL lighting up when a malfunction is detected, the applicable Diagnostic Trouble Codes (DTCs)
prescribed by SAE J2012 are recorded in the ECM memory.
If the malfunction does not reoccur in 3 consecutive trips, the MIL goes off automatically but the DTCs remain recorded in the ECM memory.