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 B1207, 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 (SECURITY)
- Remove the SECURITY 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 REFERENCETester Connection Condition Specified Condition SECURITY fuse Always Below 1 Ω
NG: REPLACE FUSE (SECURITY)
OK: Go to Next Step
- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - BATTERY AND BODY GROUND)
- Disconnect the P33 connector.
- Measure the voltage and resistance according to the value(s) in the table below.
Standard Voltage
VOLTAGE SPECIFICATIONTester Connection Condition Specified Condition P33-1 (+B1) - Body ground Always 11 to 14 V Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition P33-17 (E) - Body ground Always Below 1 Ω
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (CERTIFICATION ECU - BATTERY AND BODY GROUND)
OK: Go to Next Step
- CHECK HARNESS AND CONNECTOR (COMMUNICATION LINE)
- Disconnect the P33, RJ and M7 connectors
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition P33-27 (MPX1) - RJ-21 (MPX1) Always Below 1 Ω P33-28 (MPX2) - M7-8 (MPX2) Always Below 1 Ω
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (See REMOVAL )