Inspection Procedure

WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.

Check MPX-B1 and D/C CUT fuse.
CHECK:

Check continuity of MPX-B1 and D/C CUT fuse.

OK:

Continuity
1. NG : Replace the failure fuse.
2. OK : Go to next step.
Check voltage between terminal SYSB and GND of rear seat control switch.
PREPARATION:

Disconnect the rear seat control switch.

CHECK:

Measure voltage between terminals SYSB and GND of rear seat control switch.

OK:

Voltage: 10 - 14 V
1. OK : Proceed to next circuit inspection shown on problem symptoms table (See PROBLEM SYMPTOMS TABLE ).
2. NG : Go to next step.
Check wireharness and connector between rear seat control switch and body ground (See COMBINATION METER SYSTEM - DIAGNOSIS ).
1. NG : Repair or replace wireharness or connector.
2. OK : Check and repair wireharness and connector between rear seat control switch and battery.