DTC P2257: Secondary Air Injection (AIR) System Control A Circuit Low
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P2257 - SECONDARY AIR INJECTION (AIR) SYSTEM CONTROL A CIRCUIT LOW
| Description: | The AIR system monitor circuit is low, indicating the electrical AIR pump is off although the electrical AIR pump was commanded on by the powertrain control module (PCM). | ||
| Possible Causes: |
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| Diagnostic Aids: | The AIR monitor circuit PCM input contains a pull up voltage through a resistance internal to the PCM. This voltage is normally held low by the resistance path through the AIR pump when the pump is off. A single electrical open circuit component such as an AIR relay coil in this multi-component circuit will not be detected by the PCM output driver, yet it will create DTC P2257. |
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| Application | Key On Engine Off | Key On Engine Running | Continuous Memory |
| All | GO to HM: Secondary Air Injection (AIR) System STEP HM37. | ||