P0131

Test 1:

Tests 2 - 6:

Test 7:

SYMPTOM
P0131-1/1 O2 SENSOR SHORTED TO GROUND

WHEN MONITORED
At engine shutdown O2 Heater Diagnostics test. Then at subsequent cold start. Cold start is defined as engine coolant below 37 °C (100 °F), ambient/battery sensor reading within 6.6 °C (44 °F), and engine coolant temperature above 88 °C (170 °F) on the previous key OFF.

SET CONDITION
The oxygen sensor signal voltage is below 0.078 volts for 5 seconds after starting engine.

POSSIBLE CAUSES
- Intermittent condition
- O2 sensor operation
- O2 sensor signal circuit shorted to ground
- O2 sensor signal circuit shorted to sensor ground circuit
- O2 sensor signal shorted to heater ground/control circuit
- PCM