Inspection Procedure

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

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - ECM)

Disconnect the D23 transponder key ECU connector.

Fig 1: Identifying Transponder Key ECU And ECU Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the A21 ECM connector.

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION

Tester Connection	Specified Condition
D23-13 (EFIO) - A21-11 (IMI)	Below 1 Ω
D23-12 (EFII) - A21-10 (IMO)	Below 1 Ω
D23-11 (EGND) - A21-9 (EOM)	Below 1 Ω
D23-13 (EFIO) or A21-11 (IMI) - Body ground	10 kΩ or higher
D23-12 (EFII) or A21-10 (IMO) - Body ground	10 kΩ or higher

Reconnect the D23 transponder key ECU connector.
Reconnect the A21 ECM connector.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE ECM