Microphone Circuit between Overhead Junction Block and Multi-display: Wiring Diagram

WARNING: This page is about a different car, the 2006 Lexus GS 430 and 2006 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Microphone Circuit Between Overhead J/B And Multi-Display - Wiring Diagram

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK MULTI-DISPLAY

Measure the voltage of the connector.

Standard voltage

TESTER CONNECTION AND SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
K47-9 (MACC) - Body ground	Engine switch on (ACC)	4 to 6 V

NG : REPLACE MULTI-DISPLAY

Fig 2: Identifying Multi-Display

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK : GO TO NEXT STEP

CHECK WIRE HARNESS (MAP LIGHT ASSEMBLY - MULTI-DISPLAY)

Disconnect the W6 light connector.
Disconnect the K47 multi-display connector.

Measure the resistance of the wire harness side connectors.

Standard resistance

TESTER CONNECTION AND SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
W6-19 (ACC) - K47-9 (MACC)	Always	Below 1 Ω
W6-3 (MI1+) - K47-11 (MIN+)	Always	Below 1 Ω
W6-2 (MIC-) - K47-10 (MIN-)	Always	Below 1 Ω
W6-19 (ACC) - Body ground	Always	10 kΩ or higher
W6-3 (MI1+) - Body ground	Always	10 kΩ or higher
W6-2 (MIC-) - Body ground	Always	10 kΩ or higher

NG : REPAIR OR REPLACE HARNESS AND CONNECTOR

Fig 3: Identifying W6 Light Connector Terminals

OK : GO TO NEXT STEP

REPLACE MAP LIGHT ASSEMBLY
1. Replace the map light assembly with a normal one and check if the same problem occurs again.
  OK : Same problem does not occur.
NG : REPLACE MULTI-DISPLAY

OK : PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN DIAGNOSTIC TROUBLE CODE CHART