DTC P0137: Secondary HO2S (Sensor 2) Circuit Low Voltage
NOTE: Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions SystemsHow to Troubleshoot the CVT System(CVT System) .
| DTC Description | Confirmed DTC | Pending DTC | Freeze Frame |
|---|---|---|---|
| P0137 Secondary HO2S (Sensor 2) Circuit Low Voltage |
DTC (PGM-FI)
- 1. Problem verification:
- 1. Turn the vehicle to the ON mode.
- 2. Clear the DTC with the HDS.
- 3. Start the engine.
- 4. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on.
- 5. Monitor the OBD STATUS for DTC P0137 in the DTCs MENU with the HDS.
DTC Description OBD STATUS P0137 Secondary HO2S (Sensor 2) Circuit Low Voltage Does the HDS indicate FAILED?
YES
The failure is duplicated. Go to step 2.
NO
If the HDS indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION, go to step 1-4 and recheck.
- 2. Determine possible failure area (secondary HO2S (Sensor 2), others):
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the following connector.
Secondary HO2S (Sensor 2) 4P connector - 3. Connect terminals A and B with a jumper wire.
Terminal A Secondary HO2S (Sensor 2) 4P connector No. 1 Terminal B Secondary HO2S (Sensor 2) 4P connector No. 2 - 4. Turn the vehicle to the ON mode.
- 5. Check the parameter(s) below with the HDS.
Signal Threshold Current conditions Values Unit Values Unit HO2S S2 Less than 0.12 V Do the current condition(s) match the threshold?
YES
Go to step 3.
NO
- 3. Determine possible failure area (short in SO2 line, short in SO2SG/SO2 SG line):
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Remove the jumper wire from the secondary HO2S (Sensor 2) 4P connector.
- 3. Turn the vehicle to the ON mode.
- 4. Check the parameter(s) below with the HDS.
Signal Threshold Current conditions Values Unit Values Unit HO2S S2 about 5.0 V Do the current condition(s) match the threshold?
YES
Go to step 4.
NO
Go to step 5.
- 4. Shorted wire check (SO2SG/SO2 SG line):
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Jump the SCS line with the HDS, and wait more than 1 minute.
- 3. Disconnect the following connector.
PCM connector C (51P) - 4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode PCM connector C (51P): disconnected Secondary HO2S (Sensor 2) 4P connector: disconnected Test point 1 PCM connector C (51P) No. 39 Test point 2 Body ground Is there continuity?
YES
Repair a short in the SO2SG/SO2 SG wire between the PCM (C39) and secondary HO2S (Sensor 2).
NO
The SO2SG/SO2 SG wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P0137 goes away and the PCM was updated, troubleshooting is complete. If DTC P0137 goes away and the PCM was substituted, replace the original PCM .
- 5. Shorted wire check (SO2 line):
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Jump the SCS line with the HDS, and wait more than 1 minute.
- 3. Disconnect the following connector.
PCM connector C (51P) - 4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode PCM connector C (51P): disconnected Secondary HO2S (Sensor 2) 4P connector: disconnected Test point 1 PCM connector C (51P) No. 38 Test point 2 Body ground Is there continuity?
YES
Repair a short in the SO2 wire between the PCM (C38) and secondary HO2S (Sensor 2).
NO
The SO2 wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P0137 goes away and the PCM was updated, troubleshooting is complete. If DTC P0137 goes away and the PCM was substituted, replace the original PCM .
