Conditions for Setting the DTC

P0133

• The control module detects that the HO2S 1 rich-to-lean and lean-to-rich transition time takes longer than a calibrated value.
• This diagnostic runs once per trip.

P0134

• The control module detects that the HO2S 1 signal voltage is between 382-525 mV for more than 30 seconds.
• This diagnostic runs continuously.

P0140 - Fast Pass Test

• During the fast pass, the HO2S 2 voltage is between 381-525 mV for longer than a calibrated amount of time within the first 90 seconds of engine run time. If the fast pass test does not report a pass, then the regular test is initiated.

P0140 - Regular Test

• During the regular test, the HO2S 2 voltage is between 390-525 mV for at least 120 seconds.
• This diagnostic runs once per trip.

P1133 and P1134

• The control module detects that the HO2S 1 voltage did not have enough switches from rich-to-lean and lean-to-rich during a 90 second monitoring period.
• This diagnostic runs once per trip.

P2A00

• The powertrain control module (PCM) detects that the loop status parameter is open.
• DTC P2A00 sets within 50 seconds when the above condition is met.
• This diagnostic runs continuously.

P2A01

• The HO2S 2 parameter is between 290-685 mV during the passive test.
• One of the following tests fail:

  Lean Intrusive Test

  • The control module detects that the HO2S 2 voltage is more than 290 mV for 11.4 seconds.
  • The control module detects that the HO2S 1 voltage is less than 100 mV.

  Rich Intrusive Test

  • The control module detects that the HO2S 2 voltage is less than 685 mV for 11.4 seconds.
  • The control module detects that the HO2S 1 voltage is more than 777 mV.
• This diagnostic runs once per trip.