Fault code P2258 is called “Secondary Air Injection System Control “A” Circuit High” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.
Technical description and explained code P2258
Error code P2258 refers to the secondary air injection system, which injects outside air into the exhaust system when starting a cold engine. This extra air helps to burn off the very rich exhaust gases that are produced when the engine is warmed up.
The secondary air injection system is based on either a belt-driven or electric pump. The pump forces ambient air into the engine exhaust system to reduce exhaust emissions.
Silicone-based, heat-resistant hoses are used to supply cold outside air to the pump. Ambient air is filtered prior to intake through an air filter housing designed specifically for the secondary air injection system.
Ambient air is supplied to the exhaust system through high-temperature silicone and steel tubing connected to holes in the exhaust pipes. One-way check valves are installed in each exhaust hose to prevent condensate from entering the pump and causing a malfunction.
The PCM controls the secondary air injection pump operation based on engine temperature, RPM, and throttle position.
If the PCM detects excessive voltage in the “A” control circuit of the secondary air injection system, code P2258 is stored. The malfunction indicator lamp (MIL) is then illuminated, which may require several ignition failure cycles.
Symptoms of vehicle malfunctions
The main signal that an error P2258 has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- The “Check engine” control lamp on the control panel will light up (the code will be stored as a fault).
- On some European vehicles, the contamination control light will illuminate.
- Noise from air pump due to mechanical wear or presence of foreign objects in it.
- The engine does not accelerate well.
- The engine may run on too enriched mixture, if an excessive amount of air enters the exhaust manifold.
- Sometimes there may be no symptoms, despite a stored fault code.
The severity of this code is not high, but the car is unlikely to pass an emissions test. Since when the error P2258 appears, the emissions will increase.
Factors that can cause this error code
The error code P2258 can mean that one or more of the following problems have occurred:
- Pump check valves have failed.
- Secondary air pump relay is faulty.
- Problem with control solenoid.
- Rupture or leak in hoses or ducts.
- Fouling in hoses, ducts, or other components.
- Moisture in pump and motor.
- Open or interrupted power supply to secondary air injection system.
- Blown secondary air injection fuse.
- Sometimes the cause is a faulty PCM module.
How to fix or reset OBD-2 code P2258
Some suggested steps for troubleshooting and fix the error code P2258:
- Connect the OBD-II scanner to the vehicle’s diagnostic connector and read all stored data and error codes.
- Before proceeding to diagnose code P2258, troubleshoot any other errors that may be present.
- Visually inspect the electrical wires and connectors related to the secondary air injection system.
- If necessary, repair or replace any shorted, broken, damaged, or corroded components.
- Check the secondary air pump relay.
- Test the secondary air pump resistance.
Diagnose and repair of problems
Code P2258 is set when there is no outside air to burn off excess hydrocarbons in the exhaust system during a cold start. This causes the voltage on the front oxygen sensor not to drop to the set level.
The diagnostic procedure requires the engine to be cold, ideally with the vehicle idling for at least 10-12 hours. After that, you must connect the diagnostic tool and start the engine.
The voltage on the front oxygen sensor should drop below 0.125 volts after about 5-10 seconds. The fault in the secondary air system will be confirmed if the voltage does not drop to this value.
If the voltage does not drop to 0.125 volts, but you can hear the air pump running, check all hoses, air lines, valves and solenoids for leaks. Also remember to check all hoses, ducts and valves for obstructions such as carbon buildup or other blockages.
If the air pump won’t turn on, check all relevant fuses, relays, wiring, and pump motor for continuity. If necessary, replace or repair failed components.
When all checks have been completed but the P2258 malfunction persists, it may be necessary to remove the exhaust manifold or cylinder head. To gain access to the system conduits for the purpose of cleaning the fouling.
On which vehicles does this problem occur most frequently
Fault code P2258 can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- BMW
- Dodge
- Ford (Focus, Fusion)
- Jaguar
- Land Rover (Range Rover)
- Mazda
- Mercury (Milan)
- Saab
Fault code P2258 can sometimes be found with other errors. The most common are the following: P0202, P2257, P2259, P2260.