P0418
Secondary Air Injection System Relay A Circuit Malfunction
Generic code
Auxiliary Emissions Control
Medium severity
Moderate repair
Free on OBD DashX
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What P0418 means
- The fault code P0418 indicates that there is an issue with the circuit that controls the relay that activates the secondary air injection system. This system injects fresh air into the engine exhaust to reduce emissions during cold start conditions.
Possible symptoms
- Illuminated check engine light
- Reduced engine power or acceleration
- Increased emissions during cold start conditions
Possible causes
- Faulty secondary air injection system relay
- Wiring or connections in the relay circuit that are damaged or corroded
- Failed engine control module (ECM)
Related parts
- Exhaust Pipe Air Injection: Air is injected into the exhaust gases for better combustion of unburnt fuel and pollutants. This allows better exhaust emission. Problems lead to harmful emissions out of limit
Possible solutions
- Replace the secondary air injection system relay
- Check and repair any damaged or corroded wiring or connections in the relay circuit
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0418 on OBD DashX
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