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 PASSENGER SIDE JUNCTION BLOCK ECU

Measure the resistance and of the ECU connector.

Fig 1: Identifying ECU Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
P5-1 (REV) - Body ground	Shift lever is on R position	10 to 14 V
P5-1 (REV) - Body ground	Shift lever is not on R	Below 1 V

NG: REPLACE PASSENGER SIDE JUNCTION BLOCK

OK: Go to next step

CHECK WIRE HARNESS (NAVIGATION ECU - PASSENGER SIDE JUNCTION BLOCK ECU)

Disconnect the N3 and P5 ECU connectors.

Fig 2: Identifying N3 And P5 ECU Connectors Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
N3-14 (REV) - P5-1 (BACK)	Below 1 Ω
N3-14 (REV) - Body ground	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR

OK: REPLACE NAVIGATION ECU