Inspection Procedure

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

INSPECT FUSE (DR/LCK, ECU-B1)

Remove the DR/LCK fuse from the main body ECU.
Remove the ECU-B1 fuse from the engine room junction block.

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

Standard resistance

FUSE (DR/LCK, ECU-B1)

Tester Connection	Condition	Specified Condition
DR/LCK fuse	Always	Below 1 Ω
ECU-B1 fuse	Always	Below 1 Ω

NG: REPLACE FUSE

OK: Go to Next Step

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

Fig 1: Identifying Main Body ECU Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the DA, DB and DD main body ECU connectors.

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

Standard voltage

MAIN BODY ECU - BATTERY AND BODY GROUND VOLTAGE

Tester Connection	Condition	Specified Condition
DB-13 (BECU) - Body ground	Always	11 to 14 V
DA-1 (ALTB) - Body ground	Always	11 to 14 V

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

Standard resistance

MAIN BODY ECU - BATTERY AND BODY GROUND RESISTANCE

Tester Connection	Condition	Specified Condition
DD-62 (GND1, GND2) - Body ground	Always	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE