Secondary Air Injection System Control Circuit High
The P2258 code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the control circuit of the secondary air injection (SAI) system. This system pumps fresh air into the exhaust manifold during cold starts to reduce emissions. A high voltage reading typically points to a short to power, a faulty relay, or a malfunctioning SAI pump. The issue can cause increased emissions and may trigger the Check Engine Light.
01. Most Common Causes
- Short to power in the SAI pump control circuit
- Faulty SAI pump relay
- Damaged SAI pump motor
- Corroded or loose electrical connectors
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Failed emissions test
- Possible rough idle or hesitation on cold start
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for additional codes.
Step 2: Visually inspect the SAI pump, relay, and wiring for damage or corrosion.
Step 3: Test the SAI pump relay and control circuit voltage with a multimeter.
Step 4: Check the SAI pump motor resistance and operation.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, it is generally safe to drive short distances, but the vehicle may fail an emissions test and the Check Engine Light will remain on. Prolonged driving may cause other issues if the pump fails completely.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, depending on the root cause. Replacing a relay or fixing wiring is on the lower end, while replacing the SAI pump can be more expensive.