Camshaft Timing Oil Control Valve Assembly - Components
Lexus IS250 IS220d GSE20 ALE20 4GR-FSE ENGINE CONTROL SYSTEM
Mass Air Flow Meter - Installation
Install a new O-ring to the MAF meter.
Mass Air Flow Meter - Removal
Remove the 11 clips and intake duct seal.
Mass Air Flow Meter - On-Vehicle Inspection
Perform confirmation driving pattern.
Mass Air Flow Meter - Components
Lexus IS250 IS220d GSE20 ALE20 4GR-FSE ENGINE CONTROL SYSTEM
Sfi System - Mil Circuit
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.
Sfi System - Cranking Holding Function Circuit
When the engine is cranking, the starter operation signal is sent to the ECM's STA terminal.
Sfi System - Fuel Pump Control Circuit
Refer to DTC P0230 .
Sfi System - Vc Output Circuit
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.
Sfi System - Ecm Power Source 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.