How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2007 Lexus GX 470. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Use these procedures to troubleshoot the multiplex communication system.
*: Use the intelligent tester.

VEHICLE BROUGHT TO WORKSHOP
CUSTOMER PROBLEM ANALYSIS CHECK
INSPECT BATTERY VOLTAGE
Standard voltage:

10 to 14 V

If the voltage is below 11V, recharge or replace the battery before proceeding.
CHECK FOR DTC*
1. Check for DTCs and note any codes that are output.
2. Delete the DTC.
3. Check if the DTC will be output once again when the problem symptom is simulated based on the noted code.
OVERALL ANALYSIS AND TROUBLESHOOTING
1. See TERMINALS OF ECU
ADJUST, REPAIR OR REPLACE
CONFIRMATION TEST
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