Inspection Procedure

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

CHECK HARNESS AND CONNECTOR (TSW- - SGND)

Disconnect the I7 navigation receiver assembly connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

STANDARD RESISTANCE

Tester Connection	Condition	Specified Condition
I7-12 (TSW-) - I7-18 (SGND)	Always	Below 1 Ω
l7-12 (TSW-) - Body ground	Always	10 kΩ or higher

Reconnect the navigation receiver assembly connector.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig 1: Identifying I7 Navigation Receiver Assembly Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER - MICROPHONE AMPLIFIER ASSEMBLY)

Disconnect the I7 navigation receiver assembly connector.
Disconnect the U7 roof console box assembly connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

STANDARD RESISTANCE

Tester Connection	Condition	Specified Condition
I7-17 (MACC) - U7-10 (ACC)	Always	Below 1 Ω
I7-19 (MIC+) - U7-9 (MI1+)
I7-20 (MIC-) - U7-8 (MIC-)
I7-17 (MACC) - Body ground	Always	10 kΩ or higher
I7-19 (MIC+) - Body ground
I7-20 (MIC-) - Body ground

Reconnect the navigation receiver assembly connector.
Reconnect the roof console box assembly connector.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig 2: Identifying I7 Navigation Receiver Assembly And U7 Roof Console Box Assembly Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to Next Step

INSPECT NAVIGATION RECEIVER ASSEMBLY (MACC VOLTAGE)

Reconnect the I7 navigation receiver assembly connector.

Measure the voltage according to the value(s) in the table below.

Standard Voltage

STANDARD VOLTAGE

Tester Connection	Switch Condition	Specified Condition
I7-17 (MACC) - Body ground	Ignition switch ACC	4 to 6 V

Reconnect the navigation receiver assembly connector.

NG: REPLACE NAVIGATION RECEIVER ASSEMBLY (See REMOVAL )

Fig 3: Identifying I7 Navigation Receiver Assembly Connector Terminals

OK: Go to Next Step

REPLACE MICROPHONE AMPLIFIER ASSEMBLY WITH ANOTHER AND CHECK
1. Replace the telephone microphone assembly with a normal one (See REMOVAL ).
2. Check if the same problem occurs again.
  OK: Malfunction disappears
NG: REPLACE ROOF CONSOLE BOX ASSEMBLY (See REMOVAL )

OK: END (MICROPHONE IS FAULTY)