Toyota Sienna Service Manual: How to proceed with troubleshooting

1 VEHICLE BROUGHT TO WORKSHOP

2 INSPECT BATTERY VOLTAGE

Standard voltage: 11 to 14 V

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

3 BASIC INSPECTION

1. Turn the ignition switch ON.
2.  Check whether or not the radio receiver turns on.

Result

4 CHECK FOR DTC

1. Check for DTCs and note any codes that are output.
2.  Delete the DTCs.
3.  Recheck for DTCs by simulating the operation indicated by the DTCs.

HINT:

•  If the system cannot enter the diagnosis mode, inspect the AVC-LAN and all the components that connect to the AVC-LAN for short circuits and repair or replace the problem part.
•  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

5 DIAGNOSTIC TROUBLE CODE CHART

Find the output code on the diagnostic trouble code chart

6 PROBLEM SYMPTOMS TABLE

Refer to the problem symptoms table

Result

7 OVERALL ANALYSIS AND TROUBLESHOOTING

1. Terminals of ECU

8 ADJUST, REPAIR OR REPLACE

9 CONFIRMATION TEST

END