1. Measure voltage between ECM/PCM connector terminal A5 and E21.

Is there 0.1 V or less?

YES | - | Repair open in the wire between the ECM/PCM (E21) and the secondary HO2S (Sensor 2), then go to Step 25 .
NO | - | Go to Step 30 .

1. Turn the ignition switch OFF.

1. Replace the secondary HO2S (Sensor 2).

1. Reconnect all connectors.

1. Turn the ignition switch ON (II).

1. Reset the ECM/PCM with the HDS.

1. Do the ECM/PCM idle learn procedure.

1. Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES | - | If DTC P0141 is indicated, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM, then go to Step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO | - | Go to Step 30 .

1. Monitor the OBD STATUS for DTC P0141 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES | - | Troubleshooting is complete.■
NO | - | If the screen indicates FAILED, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM, then go to Step 1 . If the screen indicates NOT COMPLETED, go to Step 28 and recheck.

1. Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM.

1. Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES | - | If DTC P0141 is indicated, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM, then go to Step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO | - | If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM. ■