Search fault codes by symptom

Pick symptoms and a vehicle type to see published fault-code sheets that list those symptoms. A symptom is not a diagnosis.

How to use this page

Choose one or more symptoms, and optionally Auto, heavy truck, or diesel. The list shows published sheets that carry those validated symptom tags, most matches first.

A symptom is not a diagnosis. The same complaint can come from several codes. Open the sheet, then confirm the fault on the vehicle with a scan tool and the service manual.

Vehicle type

Symptoms

Matching sheets

Select at least one symptom to see sheets.