How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2006 Lexus RX 400h. However, it is still accessible from the selected car via links, so may be relevant.

VEHICLE BROUGHT TO WORKSHOP
INSPECT BATTERY VOLTAGE
Standard voltage: 11 to 14 V

If the voltage is below 11 V, recharge or replace the battery before proceeding.

INSPECT COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX COMMUNICATION SYSTEM (BEAN)

Using the intelligent tester, check if the Multiplex Communication System (MPX) is functioning normally.

Result

MPX DTC RESULT

Result	Proceed to
MPX DTC is not output	A
MPX DTC is output	B

B: Go to MULTIPLEX COMMUNICATION

A: Go to next step.

BASIC INSPECTION

Turn the ignition switch ON.

Check whether or not the radio receiver turns on.

Result

RADIO RECEIVER TURNS RESULT

Result	Proceed to
Radio receiver turns on	A
Radio receiver does not turn on	B

B: Go to step 6

A: Go to next step.

CHECK FOR DTC

Check for DTCs and note any codes that are output.
Delete the DTCs.

Recheck by simulating the operation indicated by the DTC.

HINT:

If the system cannot enter the diagnosis mode, inspect each AVC-LAN communication signal and repair or replace the problem parts.
Even if the malfunction symptom is not confirmed, check the DTCs. This is because the system stores past DTCs.

Check and clear past DTCs. Then check for DTCs.

Result

DTC OUTPUT RESULT

Result	Proceed to
DTC is output again	A
DTC is not output	B

B: Go to step 7

A: Go to next step.

DIAGNOSTIC TROUBLE CODE CHART
Find the output code on the diagnostic trouble code chart (See DIAGNOSTIC TROUBLE CODE CHART ).

NEXT: Go to step 9

PROBLEM SYMPTOMS TABLE

Refer to PROBLEM SYMPTOMS TABLE .

Result

PROBLEM SYMPTOMS TABLE RESULT

Result	Proceed to
Fault is not listed in problem symptoms table	A
Fault is listed in problem symptoms table	B

B: Go to step 9

A: Go to next step.

OVERALL ANALYSIS AND TROUBLESHOOTING
1. TERMINALS OF ECU
ADJUST, REPAIR OR REPLACE
CONFIRMATION TEST NEXT
NEXT: END