DTC Troubleshooting

DTC P0098: IAT Sensor 2 Circuit High Voltage

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).
2. Check IAT SENSOR 2 in the DATA LIST with the HDS.

Is about - 40 °F (- 40 °C) or less, or 4.90 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 IAT sensor 2 and the PCM.

3. Turn the ignition switch OFF.
4. Disconnect IAT sensor 2 2P connector.




5. Connect IAT sensor 2 2P connector terminals No. 1 and No. 2 with a jumper wire.
6. Turn the ignition switch ON (II).
7. Check IAT SENSOR 2 in the DATA LIST with the HDS.

Is about - 40 °F (- 40 °C) or less, or 4.90 V or more indicated?

YES - Go to step 8.

NO - Go to step 20.

8. Turn the ignition switch OFF.
9. Remove the jumper wire from IAT sensor 2 2P connector.
10. Turn the ignition switch ON (II).




11. Measure voltage between IAT sensor 2 2P connector terminal No. 2 and body ground.

Is there about 5 V?

YES - Go to step 12.

NO - Go to step 16.

12. Turn the ignition switch OFF.
13. Jump the SCS line with the HDS.
14. Disconnect PCM connector B (44P).




15. Check for continuity between IAT sensor 2 2P connector terminal No. 1 and PCM connector terminal B33.

Is there continuity?

YES - Go to step 27.

NO - Repair open in the wire between the PCM (B33) and IAT sensor 2, then go to step 22.

16. Turn the ignition switch OFF.
17. Jump the SCS line with the HDS.
18. Disconnect PCM connector B (44P).




19. Check for continuity between IAT sensor 2 2P connector terminal No. 2 and PCM connector terminal B31.

Is there continuity?

YES - Go to step 27.

NO - Repair open in the wire between the PCM (B31) and IAT sensor 2, then go to step 22.

20. Turn the ignition switch OFF.
21. Replace IAT sensor 2.
22. Reconnect all connectors.
23. Turn the ignition switch ON (II).
24. Reset the PCM with the HDS.
25. Do the PCM idle learn procedure.
26. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0098 indicated?

YES - Check for poor connections or loose terminals at IAT sensor 2 and the PCM, then go to step 1.

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

27. Reconnect all connectors.
28. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
29. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0098 indicated?

YES - Check for poor connections or loose terminals at IAT sensor 2 and the PCM. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.

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