LIGHTING SYSTEM - AFS ECU Power Source Circuit

DESCRIPTION

This circuit detects the state of the engine switch. The AFS ECU receives it from the engine switch.

Lighting System - Afs Ecu Power Source Circuit. LIGHTING. Lexus IS250 IS220d GSE20 ALE20

1.INSPECT AFS ECU

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

Standard voltage:
Tester Connection Condition Specified Condition
A27-1 (E1) - A27-2 (IG) Engine switch off Below 1 V
A27-1 (E1) - A27-2 (IG) Engine switch on (IG) 10 to 14 V

NG

OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

2.CHECK WIRE HARNESS (AFS ECU - BODY GROUND)

Disconnect the A27 AFS ECU connector.

Measure the resistance according to the value(s) in the table below.

Standard resistance:
Tester Connection Condition Specified Condition
A27-1 (E1) - Body ground Always Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (AFS ECU - BODY GROUND)

OK

3.INSPECT AFS ECU

Disconnect the A27 AFS ECU connector.

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

Standard voltage:
Tester Connection Condition Specified Condition
A27-1 (E1) - A27-2 (IG) Engine switch on (IG) 10 to 14 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (AFS ECU - BATTERY)

OK

REPLACE AFS ECU

LEXUS IS250, IS220d / GSE20 ALE20

Tester Connection	Condition	Specified Condition
A27-1 (E1) - Body ground	Always	Below 1 Ω

Tester Connection	Condition	Specified Condition
A27-1 (E1) - A27-2 (IG)	Engine switch on (IG)	10 to 14 V