Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus LS 600hL. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FUSE (D-IG1-2)

Remove the D-IG1-2 fuse from the main body ECU
Measure the resistance according to the value (s) in the table below

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
D-IG1-2 fuse	Always	Below 1 Ω

NG: REPLACE FUSE

OK: Go to next step

CHECK HARNESS AND CONNECTOR (DRIVING SUPPORT ECU - BATTERY AND BODY GROUND)

Disconnect the A33 ECU connector.

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

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
A33-13 (B) - Body ground	Power switch ON (IG)	11 to 14 V
A33-13 (B) - Body ground	Power switch OFF	Below 1 V

Fig 1: Identifying Driver Support ECU A33 Connector

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

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
A33-25 (GND) - Body ground	Always	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

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