The P2059: Reductant Injection Air Pump Control Circuit/Open refers to a problem where the control circuit for the reductant injection air pump is open. This issue may affect the system’s ability to properly inject reductant into the exhaust, leading to higher emissions. Common causes include an open circuit, faulty air pump, or issues with wiring and connectors.
P2059 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P2059: Reductant Injection Air Pump Control Circuit/Open |
| Is it serious? | Yes, this can prevent the proper function of the emissions control system, increasing emissions. |
| Possible causes | – Open circuit in the air pump control circuit – Faulty air pump or wiring – Connector issues |
| How to diagnose? | – Inspect the control circuit for open conditions – Test the air pump – Check wiring and connectors |
P2059 Meaning
The P2059 code indicates an open circuit in the reductant injection air pump control circuit. The air pump plays a critical role in delivering reductant (e.g., diesel exhaust fluid) into the exhaust system to reduce harmful emissions. When there is an open circuit, the pump cannot function correctly, leading to inefficient emissions control.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional codes that could help further diagnose the issue. | OBD-II Scanner |
| Inspect Control Circuit | Inspect the air pump control circuit for any signs of an open circuit, including loose connections or visible damage. | Flashlight, Safety Gloves |
| Test the Air Pump | Use a diagnostic tool to test the functionality of the air pump and ensure it operates within the manufacturer’s specifications. | Multimeter, Diagnostic Tool |
| Check Wiring and Connectors | Inspect the wiring and connectors for any breaks, corrosion, or disconnections that may result in an open circuit. | Flashlight, Multimeter |
| Clear the Code and Test Drive | After completing repairs, clear the fault code using an OBD-II scanner and perform a test drive to ensure the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | After the test drive, re-scan the vehicle to ensure that the P2059 code does not reappear. If it does, further diagnostics may be necessary. | OBD-II Scanner |
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