Code result
P0418
Secondary Air Injection System Relay A Circuit Malfunction
Moderate severity
What it means
General electrical fault in the secondary air injection pump relay A circuit. Without the relay, the air pump cannot be commanded and the system cannot complete its cold-start function.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Air pump relay failed
highOne of the most commonly reported causes for this code — check this first.
Wiring or connector fault
mediumA plausible cause — test and verify before replacing parts.
Related help
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