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Engine Control Module

Engine Control Module (ECM) monitors and controls vehicle emissions, fuel system, ignition system and other various systems by using input signals from various input devices. ECM processes input signals from input devices and delivers output signals to various components for controlling system operation to achieve optimum engine performance for all operating conditions. See INPUT DEVICES  and OUTPUT SIGNALS  . ECM contains a fail-safe function which is used in case of sensor or switch failure. Fail-safe function uses preprogrammed values to provide a limp-in mode for minimal driveability. If a failure exists, ECM will inform the driver by illuminating the Malfunction Indicator Light (MIL).

NOTE: MIL may also be referred to as CHECK ENGINE light. MIL is displayed as an engine icon on instrument cluster on instrument panel.

ECM contains a self-diagnostic system which may store a Diagnostic Trouble Code (DTC) if an electronic control system failure exists. DTC may be retrieved from ECM for system diagnosis by using Toyota hand-held tester or a scan tool. See SELF-DIAGNOSTIC SYSTEMS . For ECM location, see Fig 1-Fig 16 .

Fig 1: Locating Engine Control Module (Avalon)
G99D52806Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Locating Engine Control Module (Camry)
G00025406Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: Locating Engine Control Module (Camry Solara 2.4L 4-Cyl.)
G00025410Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 4: Locating Engine Control Module (Camry Solara 3.0L V6)
G00025414Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 5: Locating Engine Control Module (Celica)
G99E52807Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 6: Locating Engine Control Module (Corolla)
G99B08290Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 7: Locating Engine Control Module (ECHO)
G99F52808Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 8: Locating Engine Control Module (Highlander)
G00028711Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 9: Locating Engine Control Module (Land Cruiser)
G99D08291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 10: Locating Engine Control Module (MR2)
G00028715Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 11: Locating Engine Control Module (Prius)
G00028719Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 12: Locating Engine Control Module (RAV4)
G00028723Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 13: Locating Engine Control Module (Sequoia & Tundra)
G99E08296Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 14: Locating Engine Control Module (Sienna)
G99H08293Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 15: Locating Engine Control Module (Tacoma 2.4L 4-Cyl. & 2.7L 4-Cyl., & 4Runner)
G99J08294Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 16: Locating Engine Control Module (Tacoma 3.4L V6)
G99C08295Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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