I'm looking for code p11a9 on star gave me this code.

Question

We are driving and our light came on we contacted OnStar and they gave us a code. But it is Saturday and everything is closed.so we need to know what the code is.

Answer 1

Hi there

DTC P11A9

• HO2S Performance - Signal Low During Moderate Load Sensor 1

P11A6 or P11A9 
 

• The engine run time is greater than 10 s.
• The engine speed is between 1,200 and 2,600 RPM.
• The intake air temperature is between -43 to +123°C (-45 to +253°F).
• The BARO pressure is between 50-110 kPa (7.25-16 psi).
• The exhaust gas temperature Sensor 2 is greater than 95°C (203°F).
• The battery voltage is greater than 11 V.
• The EGR is commanded ON and the exhaust gas temperature sensor 2 is between 100-1,000°C (212-1,832°F).
• The DPF regeneration is not active.
• The DTCs run continuously once the above conditions are met.