DTC Priorities for Troubleshooting

Priorities for troubleshooting

When multiple DTCs occur, find out the order in which the DTCs should be inspected by checking the component's DTC chart. If no instructions are written in the DTC chart, check DTCs in the following order of priority:
1. DTCs other than fuel trim malfunction DTCs (P0171 and P0172) and misfire DTCs (P0300 to P0306).
2. Fuel trim malfunction DTCs (P0171 and P0172).
3. Misfire DTCs (P0300 to P0306).