DTC P0137: Secondary HO2S (Sensor 2) Circuit Low Voltage
- Reset the ECM/PCM (see page 11-312).
- Start the engine. Hold the engine at 3,000 rpm (min-1) with no load (in Park or neutral) until the radiator fan comes on.
- Check the secondary HO2S (Sensor 2) output voltage at 3,000 rpm (min-1) with the scan tool.
Does the voltage stay at 0.3 V or less?
YES |
- Go to step 4. |
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/PCM. |
- Turn the ignition switch OFF.
- Disconnect the secondary HO2S (Sensor 2) 4P connector.
- Turn the ignition switch ON (II).
- Check the secondary HO2S (Sensor 2) output voltage with the scan tool.
Does the voltage stay at 0.3 V or less?
YES |
- Go to step 8. |
NO |
- Replace the secondary HO2S (Sensor 2). |
- Turn the ignition switch OFF.
- Disconnect ECM/PCM connector E (31P).
- Check for continuity between the secondary HO2S (Sensor 2) 4P connector terminal No. 2 and body ground.
Is there continuity?
YES |
- Repair short in the wire between the ECM/PCM (E2) and the secondary HO2S (Sensor 2). |
NO |
- Substitute a known-good ECM/PCM and recheck (see page 11-313). If symptom/indication goes away, replace the original ECM/PCM. |
