Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus GX 470. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT FUSE (ACC, RADIO NO. 1)

Disconnect the ACC fuse from the driver side junction block.
Disconnect the RADIO NO. 1 fuse from the engine room relay block.

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

Standard resistance

FUSE (ACC, RADIO NO. 1)

Tester Connection	Condition	Specified Condition
ACC fuse	Always	Below 1 Ω
RADIO NO. 1 fuse	Always	Below 1 Ω

NG: REPLACE FUSE

OK: Go to Next Step

INSPECT RELAY (Marking: ACC CUT)

Disconnect the ACC CUT relay from the engine room relay block.

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

Standard resistance

RELAY (MARKING: ACC CUT)

Tester Connection	Condition	Specified Condition
3 - 4	Always	Below 1 Ω
3 - 4	Battery voltage is applied to terminal 1 - 2	10 kΩ or higher

Fig 1: Identifying Relay (Marking: ACC CUT)

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NG: REPLACE RELAY

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (NAVIGATION ECU - BATTERY AND BODY GROUND)

Disconnect the N8 ECU connector.

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

Standard resistance

NAVIGATION ECU - BATTERY AND BODY GROUND RESISTANCE

Tester Connection	Condition	Specified Condition
N8-15 (GND) - Body ground	Always	10 kΩ or higher

Fig 2: Identifying Harness & Connector (Navigation ECU - Battery & Body Ground)

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

Standard voltage

NAVIGATION ECU - BATTERY AND BODY GROUND VOLTAGE

Tester Connection	Condition	Specified Condition
N8-1 (+B) - Body ground	Always	11 to 14 V
N8-13 (ACC) - Body ground	Ignition switch ACC	11 to 14 V
N8-13 (ACC) - Body ground	Ignition switch OFF	Below 1 V

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

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