DTC P0138: Secondary HO2S (Sensor 2) Circuit High Voltage

1. Turn the ignition switch ON (II).

1. Clear the DTC with the HDS.

1. Start the engine. Hold the engine speed at 3,000 rpm (min −1 ) without load (in Park or neutral) until the radiator fan comes on, then let it idle.

1. Check the HO2S S2 in the DATA LIST with the HDS.

Does the voltage stay at 0.75 V or more?

YES | - | Go to Step 7 .
NO | - | Go to Step 5 .

1. Test-drive under these conditions:
   - Engine coolant temperature above 70 °C (158 °F)
   - A/T in D position (M/T in 4th gear)
   - Engine speed at 2,000−3,000 rpm (min −1 )
   - Drive about 10 minutes, then decelerate (with the throttle fully closed) for 5 seconds

1. Monitor the OBD STATUS for DTC P0138 in the DTCs MENU with the HDS.

Does the screen indicate FAILED?

YES | - | Go to Step 19 .
NO | - | If the screen indicates PASSED, intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the secondary HO2S sensor (Sensor 2) and the ECM/PCM. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to Step 5 and recheck.

1. Turn the ignition switch OFF.

1. Disconnect the secondary HO2S (Sensor 2) 4P connector.

1. Connect secondary HO2S (Sensor 2) 4P connector terminals No. 1 and No. 2 with a jumper wire.

1. Turn the ignition switch ON (II).

1. Check the HO2S S2 in the DATA LIST with the HDS.

Does the voltage stay at 0.75 V or more?

YES | - | Go to Step 12 .
NO | - | Go to Step 19 .

1. Turn the ignition switch OFF.

1. Jump the SCS line with the HDS.

1. Disconnect ECM/PCM connector E (31P).