During traction control system DTC checks, the technician should

• A. Use Generic Code Lists
• B. Follow the Diagnostic DTC Symptom Flow Charts
• C. Ignore DTCs If No Code
• D. Use Only Manufacturer Notes

Answer: (B)

When diagnosing traction control DTCs, you follow the Diagnostic DTC Symptom Flow Charts. These charts guide you from the specific symptom or stored code into a logical sequence of checks, using the vehicle’s own diagnostic logic rather than guesswork. They lay out which tests to perform, in what order, and what data to look for from sensors, actuators, and the control modules. This helps you correctly isolate faults in a system where multiple components—like wheel speed sensors, the ABS/ESP modulator, and the traction control logic—interact, and where codes can be shared across different functions.

Relying on generic code lists can lead you astray because those lists don’t account for the exact symptom context, the vehicle’s architecture, or the sequence of tests the system requires. Ignoring DTCs when no code is present isn’t appropriate either, since symptom-driven flow charts often include checks that reveal faults even when no stored code exists. While manufacturer notes are useful, they’re supplementary to the structured diagnostic flow; the flow charts provide the methodical roadmap you need to pinpoint the fault reliably.