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 NAVIGATION ECU (MUT2 VOLTAGE)
- Measure the voltage of the ECU connector.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard voltage
TESTER CONNECTION SPECIFIED CONDITION CHARTTester Connection Condition Specified Condition N3-15 (MUT2) - N3-17 (GND1) Voice guidance ON Below 1 V
NG: REPLACE NAVIGATION ECU
OK: Go to next step
- Measure the voltage of the ECU connector.
- CHECK WIRE HARNESS (NAVIGATION ECU - STEREO COMPONENT AMPLIFIER AND BODY GROUND)
- Disconnect the N3 ECU connector.
- Disconnect the N6 amplifier connector.
- Measure the resistance of the wire harness side connectors.
Standard resistance
TESTER CONNECTION SPECIFIED CONDITION CHARTTester Connection Specified Condition N3-15 (MUT2) - N6-4 (NAVI) Below 1 Ω N3-17 (GND1) - Body ground Below 1 Ω N3-15 (MUT2) - Body ground 10 kΩ or higher
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: Go to next step
- CHECK NAVIGATION AMPLIFIER (NAVO VOLTAGE)
- Measure the voltage of the amplifier connector.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard voltage
TESTER CONNECTION SPECIFIED CONDITION CHARTTester Connection Condition Specified Condition N6-11 (NAVO) - N6-8 (GND) Voice guidance ON Below 1 V
NG: REPLACE NAVIGATION AMPLIFIER
OK: Go to next step
- Measure the voltage of the amplifier connector.
- CHECK WIRE HARNESS (NAVIGATION AMPLIFIER - STEREO COMPONENT AMPLIFIER AND BODY GROUND)
- Disconnect the N6 and S23 amplifier connectors.
- Measure the resistance of the wire harness side connectors.
Standard resistance
TESTER CONNECTION SPECIFIED CONDITION CHARTTester Connection Specified Condition N6-11 (NAVO) - S23-9 (N-MU) Below 1 Ω N6-8 (GND) - Body ground Below 1 Ω N6-11 (NAVO) - Body ground 10 kΩ or higher
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE