Symptom Troubleshooting Versus DTC Troubleshooting

Some symptoms will not set DTCs or cause the A/T gear position indicator to blink. If the MIL was reported ON or the A/T gear position indicator has been blinking, check for DTCs. If the vehicle has an abnormal symptom, and there are no DTCs stored, do the symptom troubleshooting. Check the list of probable cause(s) for the symptom, in the sequence listed, until you find the problem.