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.

INSPECT FUSE (MPX-B2)
1. Remove the MPX-B2 fuse from the passenger side junction block.
2. Measure the resistance of the fuse.
  Standard resistance: Below 1 Ω
NG: REPLACE FUSE

OK: Go to next step.

CHECK WIRE HARNESS (TIRE PRESSURE MONITOR RECEIVER - BATTERY AND BODY GROUND)

Disconnect the T9 receiver connector.

Fig 1: Identifying T9 Receiver Connectors Terminal
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the voltage and resistance of the wire harness side connector.

Standard voltage

VOLTAGE SPECIFICATION

Tester Connection	Specified Condition
T9-1 (+B) - Body ground	10 to 14 V

Standard resistance

RESISTANCE SPECIFICATION

Tester Connection	Specified Condition
T9-6 (GND) - Body ground	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR

OK: Go to next step.

CHECK RESISTANCE OF COMMUNICATION LINE

Disconnect the A9 and G3 ECU connectors.
Disconnect the T9 receiver connector.

Fig 2: Identifying A9 And G3 ECU Connectors And T9 Receiver Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance of the wire harness side connectors.

Standard resistance

RESISTANCE SPECIFICATION

Tester Connection	Specified Condition
T9-2 (MPX1) - G3-5 (MPI1)	Below 1 Ω
T9-3 (MPX2) - A9-10 (MPX-)	Below 1 Ω

Result

RESULT CHART

Result	Proceed to
Both are OK	A
One is OK	B
Both are NG	C

B: REPLACE TIRE PRESSURE MONITOR RECEIVER ASSEMBLY AND REPAIR OR REPLACE HARNESS AND CONNECTOR

C: REPAIR OR REPLACE HARNESS AND CONNECTOR

A: REPLACE TIRE PRESSURE MONITOR RECEIVER ASSEMBLY