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-IG, MPX-B1, WIP and P B/ANC fuse.
CHECK:

Check continuity of MPX-IG, MPX-B1, WIP and P B/ANC fuse.

OK:

Continuity
1. NG : Replace the failure fuse.
2. OK : Go to next step.
Check voltage between terminal MPX-B, MPX-IG, WIP, P B/ANC, ACC and GND of passenger side junction block.
PREPARATION:

Turn the ignition switch ON.

CHECK:

Measure voltage between terminals MPX-IG, ACC and GND and body ground of the passenger side J/B.

PREPARATION:
1. Turn the ignition switch OFF.
2. Disconnect the passenger side junction block.
CHECK:

Measure voltage between terminals MPX-B, WIP, P B/ANC and GND and body ground of the passenger side J/B.

OK:

Voltage: 10 - 14 V
1. OK : Proceed to next circuit inspection shown on problem symptom table (See PROBLEM SYMPTOMS TABLE ).
2. NG : Go to next step.
Check wire harness and connector between passenger side J/B ECU and body ground (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ).
1. NG : Repair or replace wire harness or connector.
2. OK : Proceed to next circuit inspection shown on problem symptom table (See PROBLEM SYMPTOMS TABLE ).