When using the intelligent tester to troubleshoot the entry & start system: Connect the intelligent tester to the DLC3 while the engine switch is off, and turn a door courtesy light switch on and off at 1.5 second intervals until communication between the tester and vehicle begins.

This circuit provides power to operate the certification ECU.

This circuit provides power to operate the ID code box.

This DTC is output when one of the following occurs: 1) the ECM detects errors in its own communications with the ID code box; 2) the ECM detects errors in the communication lines; or 3) the ECU communication ID between the ID code box and ECM is different and an engine start is attempted. Before troubleshooting for this DTC, make sure no certification ECU DTCs are present. If present, troubleshoot the certification ECU DTCs first.

This DTC is output when the ID code box dose not respond to a verification request signal from the ECM.

This DTC is output when the ID code box detects an internal malfunction.

This DTC is output when LIN communication from the certification ECU stops for a certain amount of time.

This DTC is output when the engine switch power source supply line is open or shorted.

This DTC is output when there is an open or short malfunction in the key coil (built into the engine switch).

Lexus IS250 IS220d GSE20 ALE20 ENGINE IMMOBILISER