Lexus IS250 IS220d GSE20 ALE20 - LIGHTING

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

PERFORM ACTIVE TEST BY INTELLIGENT TESTER

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - BATTERY)

LIGHTING SYSTEM - Door Mirror Foot Light Circuit

DESCRIPTION

The turning on and off of the door mirror foot lights is controlled by the main body LH based on various signals received through BEAN communication.


The main body ECU LH includes a MOS-FET (Metal Oxide Semiconductor - Field Effect Transistor) circuit that fades the door mirror foot lights in and out by duty control.


This MOS-FET circuit has an overheat protection function as a fail-safe. If the main body ECU LH becomes excessively hot, the door mirror foot lights turn off and remain off.


Normal operation will resume when the conditions required to turn on the door mirror foot lights are met again.


WIRING DIAGRAM

Lighting System - Door Mirror Foot Light Circuit. LIGHTING. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

1.PERFORM ACTIVE TEST BY INTELLIGENT TESTER

Connect the intelligent tester to the DLC3.

Turn the engine switch on (IG).

Turn the intelligent tester main switch on.

Select the item(s) below in the ACTIVE TEST, and check the operation.

ACTIVE TEST: Body No. 3 (Main body ECU LH)
ItemTest DetailsDiagnostic Note
Exterior Foot Light OperationDoor mirror foot lights ON / OFF-
  • OK:
  • Door mirror foot lights come on.
  • HINT:
  • The door mirror foot lights RH and LH share the same power source. If either of the lights does not come on, there may be a problem in the part of the circuit that relates to that light. Therefore, inspect that part of the circuit.
NG
Go to step 2
OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
2.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - BATTERY)
Lighting System - Door Mirror Foot Light Circuit. LIGHTING. Lexus IS250 IS220d GSE20 ALE20

Disconnect the Q1 main body ECU LH connector.

Measure the voltage according to the value(s) in the table.

  • Standard voltage:
  • Tester ConnectionConditionSpecified Condition
    Q1-4 (LCTY) - Body groundAlways10 to 14 V
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)
LEXUS IS250, IS220d / GSE20 ALE20