Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT EFI RELAY (Marking: EFI)

Remove the EFI relay from the engine room No. 2 relay block.

Fig 1: Identifying EFI Relay
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance of the relay.

Standard resistance

RESISTANCE SPECIFICATION

Tester Condition	Specified Condition
3 - 5	10 kΩ or higher
3-5	Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

NG: REPLACE EFI RELAY

OK: Go to Next step

CHECK WIRE HARNESS (EFI RELAY - ECM, BATTERY AND BODY GROUND)

Remove the EFI relay from the engine room No. 2 relay block.
Disconnect the E4 and E6 ECM connectors.

Fig 2: Identifying EFI Relay And E4, E6 Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the voltage of the wire harness side connector.

Standard voltage

VOLTAGE SPECIFICATION

Tester Connection	Specified Condition
EFI relay terminal 5 - Body ground	10 to 14 V

Measure the resistance of the wire harness side connectors.

Standard resistance

RESISTANCE SPECIFICATION

Tester Connection	Specified Condition
EFI relay terminal 2 - E6-13 (MREL)	Below 1 Ω
EFI relay terminal 1 - Body ground	Below 1 Ω
EFI relay terminal 3 - E6-6 (+B)	Below 1 Ω
EFI relay terminal 3 - E6-5 (+B1)	Below 1 Ω
E4-2 (E01) - Body ground	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR

OK: REPLACE ECM