DTC Troubleshooting

DTC P0103: MAF Sensor Circuit High Voltage ('03-04 SULEV, LX-P models and '05-07 models)

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

1. Turn the ignition switch ON (II), and wait 2 seconds.
2. Check the MAF SENSOR in the DATA LIST with the HDS.

Is about 202 gm/s or 4.89 V or more indicated?

YES - Go to step 3.

NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the MAF sensor and the ECM/PCM.

3. Turn the ignition switch OFF.
4. Jump the SCS line with the HDS.
5. Disconnect the MAF sensor/IAT sensor 5P connector.
6. Disconnect ECM/PCM connector C (22P).




7. Connect MAF sensor/IAT sensor 5P connector terminal No. 4 to body ground with a jumper wire.




8. Check for continuity between ECM/PCM connector terminal C21 and body ground.

Is there continuity?

YES - Go to step 9.

NO - Repair open in the wire between the ECM/PCM (C21) and the MAF sensor, then go to step 15.

9. Reconnect ECM/PCM connector C (22P).
10. Reconnect the MAF sensor/IAT sensor 5P connector.
11. Start the engine. Hold the engine speed at 2,000 rpm without load (in Park or neutral).




12. Measure voltage between ECM/PCM connector terminal C22 and body ground.

Is there about 1.5 V?

YES - Go to step 20.

NO - Go to step 13.

13. Turn the ignition switch OFF.
14. Replace the MAF sensor/IAT sensor.
15. Reconnect all connectors.
16. Turn the ignition switch ON (II).
17. Reset the ECM/PCM with the HDS.
18. Do the ECM/PCM idle learn procedure. Programming and Relearning
19. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0103 indicated?

YES - Check for poor connections or loose terminals at the MAF sensor and the ECM/PCM, then go to step 1.

NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

20. Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM.
21. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0103 indicated?

YES - Check for poor connections or loose terminals at the MAF sensor and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then recheck. If the ECM/PCM was substituted, go to step 1.

NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.