Certification ECU Power Source Circuit: Procedure

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT CERTIFICATION ECU

Disconnect the D39 certification ECU connector.

Fig 1: Identifying D39 Certification ECU Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Voltage

Tester Connection	Condition	Specified Condition
D39-1 (+B1) - Body ground	Always	10 to 14 V
D39-18 (IG) - Body ground	Engine switch OFF → ON (IG)	Below 1 V → 10 to 14 V
D39-19 (ACC) - Body ground	Engine switch OFF → ON (ACC)	Below 1 V → 10 to 14 V

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

Resistance

Tester Connection	Condition	Specified Condition
D39-17 (E) - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

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