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 B1289, 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 (FR P/SEAT RH, MPX-B)
- Remove the FR P/ SEAT RH fuse from the main body ECU RH (cowl side junction block RH).
- Remove the MPX-B fuse from engine room relay block No. 1.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition FR P/SEAT RH fuse Always Below 1 Ω MPX-B fuse Always Below 1 Ω
NG: REPLACE FUSE (FR P/SEAT RH, MPX-B)
OK: Go to Next Step
- CHECK HARNESS AND CONNECTOR (FRONT POWER SEAT SWITCH RH - BATTERY AND BODY GROUND)
- Disconnect the T6 and T7 connectors.
- Measure the voltage and resistance according to the value(s) in the table below.
Standard Voltage
VOLTAGE SPECIFICATIONTester Connection Condition Specified Condition T6-5 (+B) - Body ground Always 11 to 14 V T7-8 (SYSB) - Body ground Always 11 to 14 V Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition T6-1 (GND) - Body ground Always Below 1 Ω
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT POWER SEAT SWITCH - BATTERY AND BODY GROUND)
OK: Go to Next Step
- CHECK HARNESS AND CONNECTOR (COMMUNICATION LINE)
- Disconnect the T7, RJ and P33 connectors
- Measure the resistance according to the value(s) in the table below
Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition T7-1(MPX1) - RJ-21 (MPX1) or P33-27 (MPX1) Always Below 1 Ω
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE FRONT POWER SEAT SWITCH RH (See REMOVAL )