Free API
P0418low severityPowertrain

Secondary Air Injection System Relay A Circuit Malfunction

on 2023 Chevrolet Bolt EUV 65 kWh Single Motor FWD · FWD

What this code means

The PCM detected a fault in the secondary air injection pump relay A circuit. This relay powers the air pump used to reduce cold-start emissions.

Symptoms

  • Check engine light on
  • Air pump not running
  • Failed emissions test

Common causes

  • Faulty air pump relay
  • Open or shorted relay wiring
  • Blown fuse
  • Faulty PCM driver

Diagnostic steps

  1. Scan and confirm P0418
  2. Test relay operation
  3. Check relay wiring and fuse
  4. Verify PCM control signal

Other Powertrain codes on this vehicle

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