Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
- Turn the ignition switch to ON (II).
- Check the BARO SENSOR in the DATA LIST with the HDS. Is about 160 kPa (47.2 in.Hg, 1,200 mmHg), or 4.49 V or more indicated? YES -Go to step 3. NO -Intermittent failure, the system is OK at this time.
- Update the ECM if it does not have the latest software (see «ECM UPDATE»(ref-351945-S31385529132009122900000) ), or substitute a known-good ECM (see «SUBSTITUTING THE ECM»(ref-221338-S28616532062006022400000) ).
- Check for Temporary DTCs or DTCs with the HDS. Is DTC P2229 indicated? YES -Check for poor connections or loose terminals at the ECM. If the ECM was updated, substitute a known-good ECM (see «SUBSTITUTING THE ECM»(ref-221338-S28616532062006022400000) ), then recheck. If the ECM was substituted, go to step 1 . NO -If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM (see «ECM REPLACEMENT»(ref-351945-S35124653042009122900000) ). If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.