Toyota Sienna Service Manual: How to proceed with troubleshooting

1 VEHICLE BROUGHT INTO A WORKSHOP

2 DIAGNOSTIC QUESTIONING AND SYMPTOM CONFIRMATION

1. Ask the customer about symptoms and confirm malfunctions.

3 CONFIRM THE SYSTEM NORMAL CONDITION

4 CHECK DTC

HINT: If the system cannot enter the diagnosis mode, inspect each AVC-LAN communication signal and repair or replace problem parts.

5 DTC CLEAR

1. Clear the DTCs and finish the diagnostic mode.

HINT: The currently output DTCs may not indicate actual malfunctions depending on the vehicle conditions.

6 RECHECK DTC

HINT:

•  If the system cannot enter the diagnosis mode, inspect the AVC-LAN and all the components that connect to the AVCLAN for short circuits.
•  Even if the malfunction symptom is not confirmed, check for diagnostic trouble codes. This is because the system stores past diagnostic trouble codes.
•  Refer to the detailed description on the diagnostic screen, as necessary.
•  Check the diagnostic trouble code and inspect the area the code indicates.

7 DIAGNOSTIC TROUBLE CODE CHART

1. Find the output code on the diagnostic trouble code chart.

8 PROBLEM SYMPTOMS TABLE

1. Find the applicable symptom code in the problem symptoms table.

HINT: If the symptom does not recur and no code is output, perform the symptom reproduction method

9 CHECK THE ECU TERMINAL ARRANGEMENT BASED ON THE MALFUNCTION SYMPTOM

10 CHECK THE CIRCUIT

1. Adjust, repair, or replace as necessary.

11 RECHECK THE DIAGNOSTIC TROUBLE CODE

HINT: After deleting the DTCs, recheck for diagnostic trouble codes.

12 PERFORM CONFIRMATION TEST

END