The P2258: Secondary Air Injection System Control ‘A’ Circuit High code indicates that there is a high voltage or signal detected in the secondary air injection system control ‘A’ circuit. This can be caused by a faulty control module, wiring problems, or issues with the connectors, affecting the proper functioning of the secondary air injection system. This system is crucial in helping to reduce exhaust emissions, especially during engine warm-up.
P2258 – Quick Overview
Code | Information |
---|---|
Meaning | P2258: Secondary Air Injection System Control ‘A’ Circuit High |
Is it serious? | Yes, as an improperly functioning secondary air injection system can lead to increased emissions and reduced efficiency in emissions control. |
Possible causes | – High voltage or signal in secondary air injection system control ‘A’ circuit – Faulty control module – Wiring issues – Connector problems |
How to diagnose? | – Measure voltage in the secondary air injection system control ‘A’ circuit – Test the control module and associated components – Inspect wiring and connectors for faults |
P2258 Meaning
The P2258: Secondary Air Injection System Control ‘A’ Circuit High code signifies that the voltage in the secondary air injection system control circuit for “A” is higher than expected. This elevated voltage might indicate a short to power, a fault in the control module, or a problem in the wiring. This secondary air injection system introduces additional air into the exhaust to reduce harmful emissions, particularly during cold starts, and high voltage in its control circuit may impair its function.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to determine if there are any additional codes present. These codes may help identify if the issue is isolated to the secondary air injection system or part of a larger fault in the vehicle. | OBD-II Scanner |
Measure Voltage in the Secondary Air Injection System Control ‘A’ Circuit | Use a multimeter to measure the voltage in the secondary air injection system control ‘A’ circuit. Compare the measured voltage with the manufacturer’s specifications. If the voltage is higher than the acceptable range, investigate further for the cause of the excessive voltage. | Multimeter, Vehicle Service Manual |
Test the Control Module and Associated Components | Use a diagnostic scanner to verify the operation of the control module that regulates the secondary air injection system. If the control module is outputting an incorrect signal, it may need to be recalibrated or replaced. | Diagnostic Scanner |
Inspect Wiring and Connectors for Faults | Visually inspect all wiring and connectors associated with the secondary air injection system. Look for signs of damage such as broken or frayed wires, corrosion, or loose connections, which could be causing high voltage. Repair or replace any faulty components. | Flashlight, Safety Gloves |
Check the Secondary Air Pump Relay | Inspect the relay controlling the secondary air pump. A faulty relay can cause continuous high voltage to be sent through the system, resulting in a high circuit code. Replace the relay if it is found to be faulty. | Relay Tester, Basic Hand Tools |
Clear the Code and Test Drive | After completing repairs, use an OBD-II scanner to clear the P2258 code. Conduct a test drive to verify that the system is functioning correctly and that the fault code does not reoccur. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure that the P2258 code has not returned. If the issue persists, further diagnostic efforts will be required to determine the underlying problem. | OBD-II Scanner |

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