DTC P0141: Secondary HO2S (Sensor 2) Heater Circuit Malfunction
- Reset the ECM (see page 11-4).
- Start the engine.
Is DTC P0141 indicated?
YES - Go to step 3.
NO - Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the secondary HO2S (Sensor 2) and at the ECM. 
- Turn the ignition switch OFF.
- Disconnect the secondary HO2S (Sensor 2) 4P connector.
- At the secondary HO2S (Sensor 2) side, measure resistance between the HO2S 4P connector terminals No. 3 and No. 4.
SECONDARY HO2S (SENSOR 2) 4P CONNECTOR
Wire side of female terminals
Is there about 6 ohms?
YES - Go to step 6.
NO - Replace the secondary HO2S (Sensor 2).
- Check continuity between body ground and the secondary HO2S (Sensor 2) 4P connector terminals No. 3 and No. 4 individually.
SECONDARY HO2S (SENSOR 2) 4P CONNECTOR
Wire side of female terminals
Is there continuity?
YES - Replace the secondary HO2S (Sensor 2).
NO - Go to step 7.
- Turn the ignition switch ON (II).
- Measure voltage between the secondary HO2S 4P connector terminals No. 3 and No. 4.
SECONDARY HO2S (SENSOR 2) 4P CONNECTOR
Terminals side of male terminals
Is there battery voltage?
YES - Go to step 9.
NO - Go to step 12.
- Turn the ignition switch OFF.
- Disconnect ECM connector E (31P).