Code Enable Criteria

DTC P0030, P0036, P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0130, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0171, P0172, P0201-P0206, P0300, P0325, P0327, P0335, P0340, P0401, P0404, P0410, P0440, P0443, P0502, P0503, P0506, P0507, P1133, P1134, P1336, P1153, P1351-P1366 or P1441 is not set.
Engine speed is more than 1000 RPM for more than 44 seconds.
Ignition voltage is more than 9 volts.
Engine run time is more than 9 minutes.
Barometric pressure is more than 10.1 psi (75 kPa).
Engine coolant temperature is 160-248°F (71-120°C).
Intake air temperature is less than 176°F (80°C).
Engine is in closed loop fuel control.
Engine speed is more than 1000 RPM for more than 44 seconds.
Warm catalyst. Fully open hood. Ensure transmission is in Park (A/T) or Neutral (M/T). Set parking brake. Start engine and raise engine speed to 1500 RPM for one minute. Return engine speed to idle.
Test catalyst. Ensure transmission is in Drive (A/T) or Neutral (M/T). Within 5-20 seconds, HO2S 1 should toggle rich more than 600 millivolts for up to 7 seconds, then it may toggle lean to less than 300 millivolts for up to 7 seconds. Using scan tool, verify that DTC P0420 has either passed or failed this ignition cycle.