DTC P0137 Or DTC P0138: Condition

DTC P0137 is set when Heated Oxygen Sensor No. 2 (HO2S-2) minimum voltage is more than .25 volts while fuel cut for 4 seconds and then engine is at idle for 6 seconds. DTC P0138 is set when maximum HO2S No. 2 output voltage is more than 2 volts for 20 seconds, or maximum HO2S-2 voltage is less than .35 volt for 8 minutes. MIL is illuminated when Engine Control Module (ECM) detects malfunction during 2 consecutive drive cycles. Possible causes are:

• ECM malfunction.
• Fuel system malfunction.
• Fuel shortage.
• HO2S No. 2 malfunction.
• HO2S No. 2 circuit malfunction.