DTC Troubleshooting

DTC Troubleshooting: P2A00, P2A03

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

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

NOTE:

- Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Initial Inspection and Diagnostic Overview

- Information marked with an asterisk (*) applies to the front bank (Bank 2).

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

2. Clear the DTC with the HDS.

3. Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) 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)

- Transmission in D

- 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, then decelerate (with the throttle fully closed) for 6 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 6.

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 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 to LOCK (0), or press the engine start/stop button to select the OFF mode.

7. Replace the A/F sensor (Sensor 1). A/F Sensor Replacement

8. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

9. Reset the PCM with the HDS.

10. Do the PCM idle learn procedure. PCM Idle Learn Procedure

11. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)

- Transmission in D

- 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, then decelerate (with the throttle fully closed) for 6 seconds

12. Check for Pending or Confirmed 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 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 Pending or Confirmed DTCs were indicated in step 12, go to the indicated DTC's troubleshooting.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the 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.