P2238

DTC P2238: A/F Sensor (Sensor 1) AFS+ Terminal Low Voltage

(2003 AT-PZEV (SULEV) and 2004-2005 models)


NOTE: Information marked with an asterisk (*) applies to 2003 ULEV model.

1. Reset the ECM with the HDS.
2. Start the engine.
3. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2238 (P1159)* indicated?

YES - Go to step 4.

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and at the ECM.

4. Turn the ignition switch OFF.
5. Wait for 1 minute. If the radiator fan is running, wait for 1 minute after it stops.
6. Disconnect the A/F sensor (Sensor 1) 4P connector and ECM connector A (31P).




7. Check for continuity between ECM connector terminal A6 and body ground.

Is there continuity?

YES - Repair short in the wire between the A/F sensor (Sensor 1) and the ECM (A6).

NO - Go to step 8.

8. Substitute a known-good A/F sensor (Sensor 1) and recheck.
9. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2238 (P1159)* indicated?

YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known good ECM, replace the original ECM.

NO - Replace the A/F sensor (Sensor 1).