LS400 Diagnosis By Symptom
When a diagnostic code cannot be confirmed or problem in BASIC TESTING cannot be confirmed, find basic symptom. For example, vehicle engine will not start. The appropriate heading matching vehicle symptom is DOES NOT START. Listed under DOES NOT START are more specific conditions. Find the specific condition which best fits your vehicle malfunction. Perform checks in order given. DO NOT skip sequence.
NOTE:
Symptom diagnosis will refer to testing using a diagnostic code chart, even if a diagnostic code was not set.