Inspection Procedure

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

HINT:

If "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTC B1279, repair the "+B or GND short malfunction of communication bus" DTCs first (See DTC B1214 SHORT TO B+ IN DOOR SYSTEM COMMUNICATION BUS MALFUNCTION; DTC B1215 SHORT TO GND IN DOOR SYSTEM COMMUNICATION BUS MALFUNCTION ).

INSPECT FUSE (ECU-IG LH)

Remove the ECU-IG LH fuse from the main body ECU LH (cowl side junction block LH)

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

Standard Resistance

RESISTANCE REFERENCE

Tester Connection	Condition	Specified Condition
ECU-IG LH	Always	Below 1 Ω

NG: REPLACE FUSE (ECU-IG LH)

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - BATTERY AND BODY GROUND)

Disconnect the R5 connector

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

Standard Voltage

VOLTAGE SPECIFICATION

Tester Connection	Switch Condition	Specified Condition
R5-21 (IG) - Body ground	Engine switch on (IG)	11 to 14 V

Standard Resistance

RESISTANCE REFERENCE

Tester Connection	Condition	Specified Condition
R5-39 (GND) - Body ground	Always	Below 1 Ω

Fig 1: Identifying R5 Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (OVERHEAD JUNCTION BLOCK - BATTERY AND BODY GROUND)

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (RAIN SENSOR - BATTERY AND BODY GROUND)

Reconnect the R5 connector
Disconnect the R7 connector

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

Standard Voltage

VOLTAGE SPECIFICATION

Tester Connection	Switch Condition	Specified Condition
R7-1 (SIG) - Body ground	Engine switch on (IG)	11 to 14 V

Standard Resistance

RESISTANCE REFERENCE

Tester Connection	Condition	Specified Condition
R7-3 (ES) - Body ground	Always	Below 1 Ω

Fig 2: Identifying R7 Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 5

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (COMMUNICATION LINE)

Disconnect the R7 and R5 connectors

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

Standard Resistance

RESISTANCE REFERENCE

Tester Connection	Condition	Specified Condition
R7-2 (MPX) - R5-37 (MPX1)	Always	Below 1 Ω

Fig 3: Identifying R7 And R5 Connector Terminal

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE RAIN SENSOR (See REMOVAL )

CHECK HARNESS AND CONNECTOR

Disconnect the R5 connector

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

Standard Resistance

RESISTANCE REFERENCE

Tester Connection	Condition	Specified Condition
R7-3 (ES) - R5-40 (GND2)	Always	Below 1 Ω

Fig 4: Identifying R5 Connector Terminal

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (OVERHEAD JUNCTION BLOCK - RAIN SENSOR)

OK: REPLACE OVERHEAD JUNCTION BLOCK