Remove the 11 clips and intake duct seal.

Perform confirmation driving pattern.

Lexus IS250 IS220d GSE20 ALE20 4GR-FSE ENGINE CONTROL SYSTEM

The MIL (Malfunction Indicator Lamp) is used to indicate malfunction detections by the ECM.

By turning the engine switch on (IG), power is supplied to the MIL circuit, and the ECM provides the circuit ground which illuminates the MIL.

When the engine is cranking, the starter operation signal is sent to the ECM's STA terminal.

Refer to DTC P0230 .

The ECM constantly generates 5 V power from the battery voltages supplied to the +B (BATT) terminal to operate the microprocessor. THe ECM also provides this power to the sensors through the VC output circuit.

When the engine switch is turned to on, the battery voltage is applied to terminal IGSW of the ECM. The ECM MREL output signal causes a current to flow to the coil, closing the contacts of the EFI MAIN relay and supplying power to terminal +B of the ECM.

If the engine switch is turned to off, the ECM holds the EFI MAIN relay ON for a maximum of 2 seconds to allow for the initial setting of the throttle valve.

The engine control unit and the transmission control unit are located inside the ECM. The engine control unit intercommunicates with the transmission control ECU with the Controller Area Network (CAN).

If there is a problem in this intercommunication, the ECM sets a DTC.

Refer to DTC P2195 .