DTC Troubleshooting

DTC P2A00: Rear A/F Sensor (Bank 1, Sensor 1) Circuit 1 Range/Performance Problem

DTC P2A03: Front A/F Sensor (Bank 2, Sensor 1) Circuit 1 Range/Performance Problem

NOTE:
- Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.
- Information marked with an asterisk (*) applies to the front bank (Bank 2).

1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
4. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
- A/T in D position (M/T in 3rd gear)
- Vehicle speed between 25 - 55 mph (40 - 88 km/h) for 5 minutes
- Drive at a steady speed between 55 - 75 mph (88 - 120 km/h) for 10 seconds

5. Monitor the OBD STATUS for DTC P2A00 and/or P2A03* in the DTCs MENU with the HDS.

Does the screen indicate FAILED?

YES - Go to step 7.

NO - If the screen indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to step 3 and recheck.

6. Turn the ignition switch OFF.
7. Replace the A/F sensor (Sensor 1).
8. Turn the ignition switch ON (II).
9. Reset the ECM/PCM with the HDS.
10. Do the ECM/PCM idle learn procedure.
11. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
- A/T in D position (M/T in 3rd gear)
- Vehicle speed between 25 - 55 mph (40 - 88 km/h) for 5 minutes
- Drive at a steady speed between 55 - 75 mph (88 - 120 km/h) for 10 seconds

12. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2A00 and/or P2A03* indicated?

YES - Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM, then go to step 1.

NO - Go to step 13.

13. Monitor the OBD STATUS for DTC P2A00 and/or P2A03* in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete. If any other Temporary DTCs or DTCs were indicated in step 12, go to the indicated DTCs troubleshooting.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM, then go to step 1. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to step 11.