Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

PERFORM ACTIVE TEST USING TECHSTREAM

Connect the Techstream to the DLC3.
Turn the engine switch on (IG).
Turn the Techstream on.
Enter the following menus: Body Electrical / AFS / Active Test.

Check the operation

AFS (AFS ECU)

ACTIVE TEST - AFS (AFS ECU)

Tester Display	Test Part	Control Range	Diagnostic Note
Drive The Leveling Motor	Leveling motor upward operation	UP/OFF	-
Drive The Leveling Motor	Leveling motor downward operation	DOWN/OFF	-

OK: Headlight leveling motor is operated.

Result

RESULT REFERENCE

Result	Proceed to
OK (When checking from Problem Symptoms Table)	A
OK (When checking from Diagnostic Trouble Code Chart)	B
NG	C

B: REPLACE AFS ECU (See AFS ECU )

C: Go to step 2

A: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (See PROBLEM SYMPTOMS TABLE )

CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING MOTOR - AFS ECU)

Fig 1: Identifying Headlight Assembly Connector Terminal B12, B2 And AFS ECU Connector Terminal A28

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the B12 and B2 headlight assembly connectors.
Disconnect the A28 AFS ECU connector

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

Standard Resistance:

LH Side (B2417)

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
A28-29 (LL1+) - B12-15 (LL1+)	Always	Below 1 Ω
A28-30 (LL1-) - B12-14 (LL1-)	Always	Below 1 Ω
A28-31 (LL2+) - B12-13 (LL2+)	Always	Below 1 Ω
A28-32 (LL2-) - B12-12 (LL2-)	Always	Below 1 Ω
A28-29 (LL1+) - Body ground	Always	10 kΩ or higher
A28-30 (LL1-) - Body ground	Always	10 kΩ or higher
A28-31 (LL2+) - Body ground	Always	10 kΩ or higher
A28-32 (LL2-) - Body ground	Always	10 kΩ or higher

RH Side (B2418)

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
A28-13 (LR1+) - B2-15 (LR1+)	Always	Below 1 Ω
A28-14 (LR1-) - B2-14 (LR1-)	Always	Below 1 Ω
A28-15 (LR2+) - B2-13 (LR2+)	Always	Below 1 Ω
A28-16 (LR2-) - B2-12 (LR2-)	Always	Below 1 Ω
A28-13 (LR1+) - Body ground	Always	10 kΩ or higher
A28-14 (LR1-) - Body ground	Always	10 kΩ or higher
A28-15 (LR2+) - Body ground	Always	10 kΩ or higher
A28-16 (LR2-) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next Step

CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING MOTOR - HEADLIGHT ASSEMBLY)

Disconnect the headlight leveling motor connector.

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

Standard Resistance:

LH Side

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
B12-15 (LL1+) - 3	Always	Below 1 Ω
B12-14 (LL1-) - 4	Always	Below 1 Ω
B12-13 (LL2+) - 1	Always	Below 1 Ω
B12-12 (LL2-) - 2	Always	Below 1 Ω
B12-15 (LL1+) - Body ground	Always	10 kΩ or higher
B12-14 (LL1-) - Body ground	Always	10 kΩ or higher
B12-13 (LL2+) - Body ground	Always	10 kΩ or higher
B12-12 (LL2-) - Body ground	Always	10 kΩ or higher

RH Side

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
B2-15 (LR1+) - 3	Always	Below 1 Ω
B2-14 (LR1-) - 4	Always	Below 1 Ω
B2-13 (LR2+) - 1	Always	Below 1 Ω
B2-12 (LR2-) - 2	Always	Below 1 Ω
B2-15 (LR1+) - Body ground	Always	10 kΩ or higher
B2-14 (LR1-) - Body ground	Always	10 kΩ or higher
B2-13 (LR2+) - Body ground	Always	10 kΩ or higher
B2-12 (LR2-) - Body ground	Always	10 kΩ or higher

Fig 2: Identifying Headlight Assembly Connector Terminal B12 And B2

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next Step

INSPECT HEADLIGHT LEVELING MOTOR (LH AND/OR RH)

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

Standard Resistance:

RH Side (B2418)

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
1 - 2	Always	5.8 to 12.5 Ω
3 - 4	Always	5.8 to 12.5 Ω

LH Side (B2417)

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
1 - 2	Always	5 8 to 12.5 Ω
3 - 4	Always	5.8 to 12.5 Ω

Fig 3: Identifying Headlight Leveling Motor Connector Terminal

NG: REPLACE HEADLIGHT LEVELING MOTOR LH OR HEADLIGHT HEADLIGHT LEVELING MOTOR RH (See HEADLIGHT ASSEMBLY )

OK: REPLACE AFS ECU (See AFS ECU )