Some 2009 Toyota Corolla vehicle may exhibit a Check Engine Light on condition with one or more of the following diagnostic codes stored in the Engine ECU... P0101 - Mass Air Flow Circuit Range Problem P0121 - Throttle / Pedal Position Sensor/Switch A Circuit range P0171 - System too Lean P0171 - System too Rich P035# - Ignition Coil "#" Primary / Secondary Circuit P2237 - Oxygen (A/F) Sensor Pumping Circuit Open P2238 - Oxygen (A/F) Sensor Pumping Circuit Low P2239 - Oxygen (A/F) Sensor Pumping Circuit High An improved Engine wire harness has been developed to address this condition. See TSB 0379-08
