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.

CHECK WIRE HARNESS (INSTRUMENT CLUSTER FINISH PANEL CENTER - NAVIGATION ECU)

Disconnect the M6 panel connector.

Fig 1: Identifying M6 Panel Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the N7 ECU connector.

Measure the resistance of the wire harness connectors.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
M6-18 (MCO-) - N7-5 (MIC-)	Below 1 Ω
M6-17 (MCO+) - N7-3 (MIC+)	Below 1 Ω
M6-18 (MCO-) - Body ground	10 kΩ or higher
M6-17 (MCO+) - Body ground	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR

OK: Go to next step

INSPECT INSTRUMENT CLUSTER FINISH PANEL SUB-ASSEMBLY CENTER

Remove the instrument cluster finish panel center.

Fig 2: Identifying Instrument Cluster Finish Panel Center Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance of the panel.

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
M6-18 (MCO-) - B-19 (MCO-)	Below 1 Ω
M6-17 (MCO+) - B-18 (MCO-)	Below 1 Ω
M6-16 (SGND) - 8-17 (SGND)	Below 1 Ω
M6-18 (MCO-) - Body ground	10 kΩ or higher
M6-17 (MCO+) - Body ground	10 kΩ or higher

NG: REPAIR OR REPLACE INSTRUMENT CLUSTER FINISH PANEL SUB-ASSEMBLY CENTER

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