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Testing 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.

To ensure correct diagnosis and repair, testing should be done in following sequence:

Record Customer Complaint

Ensure all customer complaints or observations are recorded. Test drive vehicle with customer when necessary for malfunction verification.

Retrieve Diagnostic Trouble Codes

Connect appropriate OBD-II scan tool. Retrieve codes and record any freeze-frame data. See RETRIEVING DIAGNOSTIC TROUBLE CODES .

Clear Trouble Codes

Clear DTCs using scan tool. See CLEARING DIAGNOSTIC TROUBLE CODES .

Perform Visual Inspection

Inspect all connectors of suspect circuit or component. Ensure all connections are clean and tight.

Confirm Symptoms & Trouble Codes

Perform road test. Determine if original symptoms are still present. Retrieve codes.

Diagnose & Repair Diagnostic Trouble Codes

Perform diagnosis and repair procedures as needed. See DIAGNOSTIC TESTS . If no codes are present, proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.).

Verification Procedure

After repairs have been completed, clear all DTCs. See CLEARING DIAGNOSTIC TROUBLE CODES . Perform road test. Ensure no codes are present and all symptoms and/or complaints have been repaired.